Abstract: Apparatus useful in surgery for holding retractors and other surgical instrumentation in a number of different positions required by a surgeon for the performance of a surgical procedure, including advanced sensing and regulation of retraction pressures and position; and incorporating a force amplification method to drive a locking mechanism in the supporting structure that utilizes a constrained, substantially incompressible, flexible solid material to yield a mechanism that is suitable for clinical use.

Abstract: A rod-shaped medical tampon for releasing an active substance, including (a) a tampon core of compressed fibers selected from the group consisting of cellulose fibers, cotton fibers, and acetate fibers; (b) a tampon cover surrounding said tampon core and being firmly bonded to one another by a glue, the tampon cover comprising a hardened collagen foam or a hardened gelatin foam impregnated with a retardant including a dissolved active substance to be released; and (c) a retrieval string connected to at least one of said tampon core and said tampon cover.

Abstract: An electrically conductive condom includes a generally cylindrical protective sheath having an open end for receiving a penis therein and an opposite closed end, the sheath being made from a thin, elastic, electrically conductive material which may be formed from a non-conductive elastic material having electrically conductive particles embedded therein. The electrically conductive material is preferably a thin elastomeric material with small conductive particles, such as carbon and/or silver particles, embedded therein. A reinforcing layer may be secured to the open end of the sheath. Optionally, a retaining strap may be secured to the reinforcing layer for retaining the sheath on a person, and quick release is provided for releasably securing the retaining strap about a person so as to releasably secure the sheath on the person.

Abstract: The invention relates to a method and an apparatus for the production of a coaxial tobacco or filter rod, a first production machine processing a strip-like first covering material and a stream of filling material to give a preformed rod which is deposited in a special magazine in order to be removed again therefrom in due course and supplied to a second production machine which brings the preformed rod together with a stream of filter or smoking material and a strip-like second covering material and processes it to form the coaxial tobacco or filter rod.

Abstract: A permanent wave rod having an elastic band to which tension is applied to hold the permanent wave rod in place against hair. Tension is applied to the elastic band by an end cap which is pivotally attached to the body of the permanent wave rod, and which is pivoted toward the body to apply tension to the elastic band, and is pivoted away from the body to release tension from the elastic band.

Abstract: A dental floss holder is provided with a slot-headed locking axle on which a spool of floss is mounted. A length of floss from the spool disposed within the holder passes through the axle slot and is spanned across two spaced prongs formed on the holder and locked to the axle by being wound on the axle beneath the slotted head after spanning. Tension is applied to the spanned floss by rotating a locking flange which is held in position by the slotted head of the locking axle to provide a taut span of floss which can be manipulated between the user's teeth.

Abstract: A vapor containment apparatus for washing an ink pump and sucker tube with a volatile ink solvent has a closed receptacle with a liquid solvent sump. An elongated sleeve encases the sucker tube within the receptacle and positions an inlet end of the sucker tube in the sump. A solvent applicator directs solvent into contact with an outer surface of the sucker tube to drain into the sump and wash the outer surface. An solvent return tube delivers solvent from the ink pump to the sump such that solvent can be drawn through the sucker tube and the pump to wash the pump and the inner surface of the sucker tube. A vacuum exhaust draws solvent vapor through openings on the elongated sleeve and the return tube and evacuates the vapor from the closed receptacle.

Abstract: A cap-shaped umbrella for carrying on the head, comprising a folding radial frame, an auxiliary folding frame pivoted to said folding radial frame, an umbrella cover stretched over said folding radial frame, a front visor connected to the peripheral edge of said umbrella cover and stretched over said auxiliary folding frame, a fastening loop assembly connected to said auxiliary folding frame for fastening the umbrella to the head, and a control mechanism controlled to stretch or collapse said folding radial frame and said auxiliary folding frame.

Abstract: A folding walker with side frames rotationally mounted on both ends of a front frame such that the side frames can rotate independently from a closed position where they are parallel to the front frame to an open position where the side frames are perpendicular to the front frame and parallel to each other. The side frames are locked in the open position by fixed plates that are mounted on the front frame. Detents with lever releases are mounted on the side frames. The detents releasably engage the fixed plates when the side frames are in the open position.

Abstract: A crutch including a tubular body, an arm support formed in an upper portion of the tubular body, and a hand grip fixed to a middle portion of the tubular body by a sleeve member which is mounted on the middle portion of the crutch and has a pair of flanges superposed with each other whereby each flange has a screw hole formed therein.

Abstract: A metal valve stem is attached to a ceramic valve plug. An elongated metal screw member has an expandable section securely wedged into a cavity in the plug as the attached screw/ceramic plug are threadably tightened on the valve stem. A first pre-wedging step presses an expander on the screw to fully bend the expander inside the ceramic cavity. The second wedging step during tightening of the screw/plug on the stem ensures uniform loading of the expander on the ceramic cavity surfaces.

Abstract: A fire safe valve which includes a body having an inlet, an outlet, a valve chamber communicating with the inlet and the outlet and having an opening, a bonnet secured to the body and having a bore therethrough with the opening of the bore communicating with the valve chamber opening and defining a back seat surrounding the bore, a valve member, a valve stem connected to the valve member and extending through the bonnet bore, a backseating shoulder on the valve stem, an actuator, the valve stem connecting to the actuator to move the valve member within the valve chamber to open and close flow through, the valve, a temperature sensitive material retaining the valve stem shoulder spaced from said bonnet bore seat during normal operations and allowing additional movement of the valve stem responsive to excessive temperatures to bring the valve stem shoulder into engagement with the bonnet bores seat to backseat and prevent flow of fluids within the valve from escaping therefrom.

Abstract: A specific gravity control apparatus 200 is disclosed which uses a plurality of electrodes 202, 204 and 206 to measure the height of a control liquid within a leg 8 to provide enhanced control of the specific gravity of the solution S. In a specific gravity control apparatus 250, a flexible diaphragm 254 isolates the solution from a control fluid. This permits a nonconductive solution to be maintained at a specific gravity by the apparatus using at least one electrode to measure the level of the control liquid which can be conductive.

Abstract: A water distribution system includes flushing hydrants having buried valve assemblies and a removable top stock carried from valve assembly to valve assembly. A vertical marker replaces the top stock when the hydrant is not in use. The buried valve assembly includes a valve urged closed by water pressure and an actuator rod extending through a spider in the top of a vertical barrel. A lock nut on the upper end of the actuator holds the valve closed even if water pressure is lost. The upper end of the vertical barrel includes an internally threaded adapter. The top stock includes a casing which is externally threaded to mate with the adapter and a second rod which is threaded to mate with the actuator rod. The hydrant is assembled by removing the lock nut and screwing the parts together while an operating screw is swung free, then swinging the operating screw into engagement with the second rod. A preferred embodiment permits water samples to be taken from the hydrant.

Abstract: A liquid treatment installation comprises apparatus for controllably treating a liquid with a liquid treatment substance. The apparatus comprises a body, a container for a liquid treatment substance in the body, and a removable closure member on the body. The installation also includes a liquid supply conduit connected to the liquid inlet of the apparatus, a liquid discharge conduit connected to the liquid outlet of the apparatus, and level control means for maintaining the liquid level in the container, thereby to dose liquid passing through the body accurately with liquid treatment substance.

Abstract: The present innovation pertains to a device with which containers, in which water collects in an unintentional manner, are automatically drained. An outer housing (2, 3), which can be inserted into the bottom of the container, is subdivided by a web (8a) into two chambers, one of which is connected to the interior of the container, and the other of which is connected to the surroundings of the container. The web encloses an opening (20) which connects the two chambers when a valve member (14) has moved away from a seat (8b) enclosing the opening. If the valve member rests on the seat, the chambers are separated from one another, and the interior space of the container is not in connection with the surroundings of the container. The movement of the valve member is controlled by the water level in the chamber which is in connection with the interior space of the container.

Abstract: A fluid flow control valve comprises a fluid heating device for supplying a heat energy to a fluid, a valve device for controlling a flow rate of the fluid, an electromagnetic coil for generating a magnetic field at the fluid heating device and the valve device so that the fluid heating device is heated to supply the heat energy to the fluid and the valve device is operated to control the flow rate of the fluid, and a power source for applying a voltage to the electromagnetic coil to generate the magnetic field, the power source supplying a current whose value fluctuates to the electromagnetic coil when the fluid heating device supplies the heat energy to the fluid.

Abstract: A pulsator device includes a water chamber having a small inlet orifice for inletting pressurized water at a relatively low rate in a continuous manner, and a large outlet orifice. An outlet valve assembly controls the large outlet orifice to open it at a relatively high chamber pressure and to close it at a relatively low chamber pressure. The outlet orifice is one end of a hollow stem passing through a wall of the water chamber. The outlet valve assembly includes an expansible/contractible control chamber and a valve member effective, in the normal expanded condition of the control chamber, to close the one end of the hollow stem, and in the contracted condition of the control chamber to open the one end of the hollow stem, and thereby to output pulses of pressurized water through the hollow stem.

Abstract: An expansion hose for power steering plants of motor vehicles. The hose includes an outer pressure hose (2) connected to an inlet side end member (1) and to an outlet side end member (3). An inner flexible hollow body (5) is arranged coaxially with pressure hose 2, and which at the inlet side is connected to a nipple plug (4) of the inlet side end member (1) and at the outlet side extends freely into the outlet side end member (3) in its outlet channel (6) with a radial clearance. The nipple plug (4) includes in addition to the axial passage (9) located at the center axial passages (10) at a radial distance outwardly therefrom and distributed circumferentially, and which lead into the annular space (8) between the outer pressure hose (2) and the inner flexible hollow body (5).

Abstract: A pipe blind including a plate for connecting to the end of a pipe, the plate having an outer edge and two parallel faces, the plate having at least one channel therein, the channel being located in the interior of the plate and having an exit port and an entrance port, the entrance port being located on one of the faces of the plate and the exit port being located on the edge of the plate.

Abstract: A diaphragm with an inflatable torus-shaped perimeter is used to seal at least one end of a stack so that debris that might be hazardous will not be released during removal of the stack. A diaphragm is inserted and inflated in the lower portion of a stack just above where the stack is to be cut such that the perimeter of the diaphragm expands and forms a seal against the interior surface of the stack.

Abstract: Between the supply bobbin and a thread tensioner supplied therefrom, which comprises a thread guide (12) which can rotate around an axis of rotation (11), are disposed a fixed thread guiding component (3) and an optical sensor (20) for monitoring the weft thread (2), which is guided by the sensor (20) and an inlet channel (18), which passes through the thread guide (12) in the axial direction, towards the thread tensioner (5). The inlet channel (18) of the thread guide (12) is eccentrically offset with respect to its axis of rotation (11), so that the section of the weft thread (2) running towards it is laterally deflected and a rotational movement which can be detected by the sensor (20) is imparted to this section, and enables a safe monitoring of the weft thread (2) with minimal thread tension. A guide piece which has a guide channel eccentrically disposed with respect to the axis of rotation (11) and can be mounted on the thread guide (12) may also be provided as means to deflect the weft thread (2).

Abstract: In a measuring weft feeder for fluid jet looms, of the type having a winding unit with adjustable cross section and comprising a cage wall formed of two sets of alternating columns mounted on reciprocally slanting flanges so as to move forward the yarn reserve into separate turns. The sets of columns (preferably divided into evenly spaced groups or sectors) are mounted on the respective flanges by way of structure adopted to adjust their radial position, this structure acting simultaneously and to an equal extent on both sets of columns and being operated by a single control member.

Abstract: An evacuating apparatus for applying suction to the underside of a microtitration diaphragm plate including a plurality of diaphragm receptacles each having an open top and a diaphragm bottom, the evacuating apparatus including a housing defining an evacuation chamber having an aperture provided in a top wall of said chamber and having associated therewith peripheral gasket means for supporting a rim of said microtitration diaphragm plate, and further comprising a carrier including support means for supporting a microtitration recipient plate including a plurality of closed bottom receptacles each having an open top and a closed bottom, said carrier being adapted to be displaced between an access position wherein said recipient plate may be positioned onto or removed from said support means, and a loading position wherein said recipient plate is disposed within said chamber below said diaphragm plate so that said diaphragm receptacles of said diaphragm plate vertically register with said closed bottom recepta

Abstract: The device for pneumatically filling toner (23) from a transport container (22) into a toner reservoir (10), from where the toner (23) is then supplied to a developer station (11) of an electrophotographic printer means, contains a settling space (12) that is in communication with the developer station (11) and contains a suction space that is separated from the settling space (12) via filter means (14) and has a means (19) that generates a low pressure allocated to it. The settling space (12) comprises a scraper means (28) that strips toner adhering to the filter means (14) via elastic scraper elements (28).

Abstract: A circular cutter wheel (34) is mounted on a work head housing (24) to rotate about a vertical axis (Y). A chain saw (76) is mounted on the housing (24) above the wheel (34). The saw (76) is mounted by a swivel device (42) which continuously rotates the saw (76) about a vertical axis (X) between a nonuse position in which the saw (76) extends over the housing (24) and a plurality of use positions in which it projects forwardly and/or laterally therefrom. The device (42) includes coaxial cylindrical housings (44, 48). The saw (76) is secured to an outer circumferential surface (82) of the outer housing (48). A motor (50) carried by the inner housing (44) rotates the outer housing (48) and saw (76).

Abstract: An edger for use with a conventional sawmill, including upper and lower chippers or cutters for forming the upper and lower edges of a board to be removed from a log, mechanical or optical sizers for automatically determining the location of the upper and lower edges of the board, and a control mechanism, responsive to the sizers, for positioning the cutters. The cutters have horizontal or vertical motors with associated blades, and the motors are mounted on carriages which ride up and down on a mast, positioned by a hydraulic cylinder. Mechanical sizing wheels are mounted on separate carriages, and the wheels are urged to contact the log's surface to determine extreme points of narrowness thereof. The extreme motion points of the sizing wheels are recorded by frictionally secured pistons which are sensed by metallic sensors which are input to the control mechanism. An electric eye causes the sizing wheels to move toward and away from the log.

Abstract: The invention relates to a rotatable blade (11) for clearing units having a plurality of teeth (1) spaced around the periphery of the blade. The teeth (1) are dismountable and/or replaceable and symmetrically shaped with several cutting edges (3), each tooth fitting into a locking recess (10) in the blade (11) with a shape corresponding to the shape of the tooth such that only one of the cutting edges (3) of the tooth projects from the blade, the remaining cutting edges (3) being located in the recess (10). The tooth (3) can be removed from the recess (10), rotated and replaced in the recess (10) such that a new cutting edge (3) projects from the blade.

Abstract: A debarker head for use in a rotary tree debarking machine has a drive shaft with a polygonal cross sectional shape and a plurality of substantially similar cutting elements with mounting apertures corresponding to the drive shaft shape and sized for slip fit engagement of the cutting elements on the drive shaft so that the cutting elements may be mounted to the drive shaft at a number of rotational positions relative to the drive shaft. Further, the cutting elements have a plurality of arms with cutting knives. The number of arms of at least some of the cutting elements is not an integer multiple of the number of sides of the mounting aperture so that a variety of cutting knife arrangements for debarking various species of logs using the same head may be obtained by adjusting the rotational position of the cutting elements relative to the drive shaft. This design of debarker head can be repaired in the field.

Abstract: A feed system with improved preposition is shown and describe wherein a prepositioning stage is located vertically above a feed stage such that movement of a wood product from the prepositioning stage to the feed stage corresponds to movement of the wood product through a transfer path having orientation corresponding to that of the height dimension of the wood product. This prepositioning configuration provides relatively more efficient movement of the wood product along its transfer path from a prepositioning stage to a feed stage as compared to prior methods where the transfer path is horizontal and the wood product moves in a direction corresponding to its relatively greater width dimension. The vertical orientation of the transfer path as provided by a prepositioning stage above a feed stage also allows for more efficient sequencing of mechanical events within the system to further contribute to improved productivity.

Abstract: A biologically resolvable blind slat and the manufacturing method therefor, wherein PVC powders serve as a basic material and are added with stabilizer, lubricant, calcium carbonate and surface-treated starch to mix therewith, the mixture being processed by a granulating machine into granules which are further heated and pressed by a press machine into strips, the strips being then cut into blind slats in a certain pattern and at a certain length.

Abstract: A partition for exhibition stands having at least one upper horizontal cross member and at least one lower horizontal cross member connected to one another by vertical uprights. A flexible material ring is disposed about the upper and lower cross members in order to bear via an upper loop on the upper member and hang via a lower loop under the lower cross member with a ballast being disposed inside the ring at the level of the lower loop so as to be located below the level of the lower cross member.

Abstract: A sleeve of woven heat resistant material is axially compressed (22) to enlarge its cross-sectional area and perimeter. A support element (24) is disposed within the sleeve (22) to support it in its enlarged perimeter condition (26). The sleeve-covered support element (18) is then disposed in a cavity (14) of a casting mold (12) and molten metal (36) is cast into the cavity (14) and around the sleeve-covered support element (18). The molten metal (36) is allowed to solidify to form a cast article (16). The support element (24) is then withdrawn from within the sleeve (22), leaving the sleeve (22) within and adhered to the walls of the passageway (20) of the article in the expanded perimeter condition (26). A tension force A is applied to the sleeve (22) forcing it to stretch into a smaller cross-sectional area and perimeter (28) and causing the sleeve (22) to detach from the casting (16) for easy removal.

Abstract: In a die-casting machine for producing castings from metals or metal alloys, which castings have a low content of gas, pores and oxides, melt is drawn by means of a vacuum out of a holding device (10) via a suction tube (11) into a casting chamber (3). A casting plunger (7) closes the inlet opening (16) to the casting chamber (3). In order to achieve as low as possible mechanical surface pressure due to flow of the melt, and fluviatile erosion of the die-side end of the inlet opening (16), and thus avoid high wear of this inlet edge or of the casting chamber with casting plunger, a planar or linear inlet cross-section (24, 27) as well as a curved deflection surface (20) on the casting plunger (7) are provided.

Abstract: A melt spinning apparatus for casting a stream of rare earth element alloy against a quench wheel includes a tundish heated by a first induction heater; a flow nozzle of boron nitride material for directing molten metal through the outlet of the tundish for distribution against the quench wheel; the nozzle includes a jet forming orifice with a flow transition entrance configured to receive a moving charge of molten metal from the inlet of the nozzle through a large longitudinal bore in the nozzle so as to reduce erosion of the nozzle orifice and to smooth flow so as to produce a uniform casting stream.

Abstract: The invention relates to a casting wheel having an interchangeable casting ring 8. The casting ring 8 is secured on an inner member 7 of the casting wheel 1 by adjustable radially and outwardly acting pressure members 17, 18 engaging with the edges of the casting ring 8. The pressure members 17, 18 center the casting ring 8, which they secure axially. The casting ring can be mounted in a problem-free manner when the pressure members are relieved of pressure.

Abstract: An improved continuous caster mold having adjustable end walls employs heating mechanisms in the portion of each of the narrow end walls above the level of molten metal contained in the mold to heat that portion of each of the end walls to a temperature more closely approximating the temperature of the end walls below the level of molten metal in the mold. The heating mechanisms tend to lower the temperature differential between the portion of the end wall below the level of molten metal and the portion of the end wall above the level of molten metal. By equalizing the temperature differential in the end wall, the thermal expansion of the end wall is made more uniform to prevent the formation of a gap between the end walls and either of the broad side walls. The improvement is also useful for reducing thermal stresses in molds having fixed, stationary end walls.

Abstract: A method of continuously casting a thin strip by pressing a pair of side walls to both side surfaces of a pair of rotating cooling drums to form a metal bath and rotating said cooling drums so as to cool a molten metal inside the metal bath and to continuously cast the thin strip, comprising the steps of pressing the side walls, which are pre-heated before the start of casting of the thin strip, to the end surface of the rotating cooling drums at a predetermined surface pressure so as to apply deformation corresponding to the shape of the end surfaces of the cooling drums to the side walls, casting under lowered press surface pressure conditions to form a necessary sliding surface required for stable casting, moving the side walls to the positions at which a wear quantity of the sliding surfaces of the side walls reach a target value, and continue casting while maintaining said positions.

Abstract: The method comprises effecting the solidification of the metal in a continuous casting ingot mould constituted by two cooled rolls (2) rotating in opposite directions and disposed in confronting relation so as to define a casting space therebetween, continuously extracting from the ingot mould a solidified steel strip (3), and, below the ingot mould, subjecting the strip to a quenching medium (6) so as to cool it sufficiently rapidly to prevent formation of austenite. This medium may be formed by a quenching bath placed in a container (4) disposed under the rolls (2) and having a bottom provided with an opening (5) for the passage of the solidified strip (3). The quenching medium may also be formed by an inert gas in the liquid state blown onto the product by nozzles. The steel strips obtained are easier to shear and coiled at the output end of the casting line owing to the absence of martensite in the ferritic matrix.

Abstract: An apparatus is disclosed for heating or cooling food articles including a chamber containing a plurality of tubular, vertically, spaced-apart support means having a fluid inlet and outlet. A plurality of removably mounted hollow plates each having a plurality of spaced-apart tubular members having a fluid sealed therein connected to first and second plenums are positioned on the support means. Supply and return header means are connected to the inlet and outlet, respectively, of the support means and by conduit to a fluid reservoir and pump to circulate a fluid transfer means through each support means. Means for heating and cooling the fluid is also provided and control means for controlling operation of the heating and cooling means individually or in a predetermined sequence and at a preselected temperature is also included. During the heating mode the fluid inside the removable plates vaporizes and condenses.

Abstract: The invention consists of a cooling system that can be worn and travel with the person using the cooling system. Flexible inter-communicating containers (such as coils), are adapted to fit body contour and function as heat removers. The containers are incorporated into clothing, or applied directly to the body. Water under a vacuum in the containers boils at low temperature and removes body heat. Vapor generated by the boiling water re-condenses into water in a communicating portable cold container, which is cooled by portable ice packs, or by endothermic chemical reactants. The degree of cooling can be controlled by regulation of the degree of the communication between the the heat remover containers and the cold condenser container. The re-condensed water returns spontaneously to the heat remover containers by force of gravity. The cooling device can be incorporated into any object which forms a direct or an indirect contact with a person using the device, such as medical casts, and cold compresses.

Abstract: Equipment for the three-stage preheating and degassing of make-up water by means of steam in a power generation installation comprises, in a first stage, a mixing chamber (3) which is located on the outside wall (2) of the condenser of the power generation installation and communicates with the condenser interior via a steam inlet (6) and steam outlet (8). In this mixing chamber, a plurality of water injection means (4) are arranged. A separation column (11) which is located upright underneath the mixing chamber (3) and which is fitted at its upper end with a water distributor (15), forms the second stage. A receiver (21), which is located underneath the separation column (11) and in which steam-dispersing means (22) are fitted and which is connected via a weir (23) to the condenser interior, forms the third stage.

Abstract: A stack comprises plates (1,2,3,4) having a zig-zag profile and defining diverging-converging passages in the flow direction (L) of the first heat-exchange medium. Each plate (1,2,3,4) has in the direction (M) perpendicular to the flow direction (M) of the first medium several rows (10) of equally spaced openings (11) accommodating tubes (11a) for a flow of the second heat-exchange medium. Each plate (1,2,3,4) has an odd number of portions (12,13) whose zig-zag profile is offset with respect to the zig-zag profile of the adjoining portion by one half of the pitch (t) of the zig-zag pattern of the profile. The rotary die set for producing the plates of this stack comprises two die rolls (19,20). The length of the evolution of the shaping surface (21,22) of each roll (19,20) is divided into an even number of portions of the same length. The zig-zag profile of each portion is offset with respect to the zig-zag profiles of the adjoining portions through one half of the pitch of the zig-zag pattern of the profile.

Abstract: A junction (16) includes a gasket (18) between a tank (12) and header (14) of a heat exchanger (10). The gasket has a substantially flat bottom surface (40), a convex upper section (42), and a lip (46) at its inner periphery (44) that extends upwardly. A concave recess (52) is interposed between the convex section and lip. The lip is positioned to fill a crevice (56) formed between the tank and header when the heat exchanger is assembled.

Abstract: The present invention is directed to a reinflatable external casing packer which is operable in three modes, including a filling mode of operation, a locking mode of operation, and a reinflation mode of operation. A valve system is provided which allows for selective filling and reinflation of the external casing packer in response to suspected or detected loss of pressure within the inflation chamber. The present invention may also be characterized as a method of placing a wellbore.

Abstract: A method of fracturing a subterranean formation in a well bore is shown in which a gellable fracturing fluid is first formed by blending together an aqueous fluid, a hydratable polymer, a suitable cross-linking agent for cross-linking the hydratable polymer to form a polymer gel and an enzyme breaker. The cross-linked polymer gel is pumped into the well bore under sufficient pressure to fracture the surrounding formation. The enzyme breaker is allowed to degrade the cross-linked polymer with time to reduce the viscosity of the fluid so that the fluid can be pumped from the formation back to the well surface. The particular enzyme breaker utilized has an activity in the range from about 2.0 to 11.0 and is effective to attack only specific linkages in the cross-linked polymer gel.

Abstract: In an oil field tubular assembly, a flapper valve permitting downward flow and blocking upward flow is closed by down-hole pressure. A pivotally mounted flapper is urged to the closed position by a spring force, which may be moderated approaching the open position to reduce flow resistance, and an offset valve inlet passage provides clearance for flapper opening and room for the pivotal mounting.

Abstract: A gage connected to the rod end of the wing cylinder on a multi-section implement senses rod end pressure at the output of the hydraulic wing control (HWC) valve. The HWC valve is engaged or disengaged using the selective control valve (SCV) in the tractor, and the gage provides a visual indication to the operator of the following modes: 1) off; 2) fold wings; 3) unfold wings; 4) field operation--push wings down; and 5) field operation--pull wings up. In field operation, the gage also provides an indication of the force with which the cylinders are pushing or pulling on the wings to affect the cutting force of the wings.

Abstract: A hand held power tool, particularly a hammer drill has a housing, a drive shaft, a rotatable tool holder, a safety coupling provided between the drive shaft and the tool holder, and a switching member supported with a bearing axis extending substantially parallel to the drive shaft and freely movable about the bearing axis in a plane extending substantially perpendicularly to the drive shaft. The switching member during a rearward rotation of the housing about an axis of the tool holder engages in the safety coupling and releasing the safety coupling.

Abstract: Screw joint tightening power tool, comprising a rotation motor (13), a power control (34), and a torque responsive override clutch (15) coupling the motor (13) to an output shaft (16). A power control (34) actuating mechanism is associated with the clutch (15) and comprises a push rod (36) which in an ON-position rests axially against a transversely movable latch (41) and is released for axial displacement toward an OFF-position at relative rotation between the driving and driven halves (20, 22) of the clutch (15). The actuating mechanism further comprises balls (45) which are disposed in peripheral pockets (48) in one of the clutch halves, either of which balls (45) is arranged to cooperate with the latch (41) to shift the latter to a push rod (36) releasing position to, thereby, make the power control (34) shut off the power supply to the motor (13) as the clutch (15) overrides at a desired torque level.