Abstract: An endless work fabric having a loop seam construction and a method of manufacture thereof is disclosed, wherein the fabric is used as a papermaker felt, a papermaker dryer fabric, a forming wire, or filter fabric. An endless belt formed of a preselected material preferably having longitudinally extending yarns included therein is collapsed upon itself to form folded ends that are stripped to expose end loops. The loops as formed in the ends of the fabric are intermeshed to define a transversely extending channel through which a pintle member is extended for joining the two ends of the folded fabric to define the endless work fabric. An alternate construction includes forming the fabric of nonwoven materials and interconnecting the ends of the collapsed fabric by a hinge-like construction through which a pintle member is extended.

Abstract: A roller cutter (28) of a drill bit (10) is retained on a journal (24) for rotation by a retainer ring (82) having external screw threads (88) which are threaded onto mating screw threads (108) on the roller cutter (28) for rotation therewith. The retainer ring (82) is mounted within a semicircular groove (68) on the journal (24) and has an inner periphery formed of a smooth arcuate surface contacting the annular groove at a position spaced at least 10.degree. from the entrance opening of the groove thereby to reduce bending stresses exerted against the root (74) of the groove (68).

Abstract: An improved overburden eliminator rock drill bit (10) is provided which includes a cylindrical body (12), cutting inserts (14) mounted thereon, and squared grooves (16) formed along the length of body (12) in a vertically tapered fashion. The taper of grooves (16) is counterclockwise in slope when viewed from the top, i.e. as viewed from above rearward end (20). Cutting face (22) engages overburden as cutting edges (30) cut overburden material so that it may be blown upwardly along grooves (16) by fluid pressure exerted through openings (32). The taper of grooves (16) serves to facilitate the upward migration of overburden material during the counter clockwise rotary action of bit (10).

Abstract: A detonation assembly for an explosive wellhead severing system which employs a battery pack lowerable through a drill string to engage and power the detonation assembly positioned within the well bore. The lowerable unit includes a biased shutter which seals the contacts from discharge of the battery pack by the surrounding fluids. The shuttered unit is lowered into contact with the receiving unit to arm the detonation assembly. Until the power unit is lowered into engagement, the severing system is not armed. In case of malfunction or misfire, the power unit can be retrieved to disarm the detonator assembly. The entire assembly is housed within the drill string to isolate the critical elements from the surrounding environment.

Abstract: The present invention discloses an improved apparatus, for trimming lawns and the like, comprising a housing having a rear ground engaging means, a cutting means extending beyond the front and substantially the left and right sides of the housing for permitting trimming of vegetation growing close to an obstruction, a skirt for preventing debris from being propelled rearwardly by the cutting means, and a removable front ground engaging means.

Abstract: A cover assembly for an opening comprises a frame and a covering. At least one elastically deformable, rod-like closing member is provided on the covering. The closing member forms one part of a locking device, the other part of which is a retaining member which includes a groove provided in the frame, in which can engage a closing finger located on the closing member accompanied by the elastic deformation of the closing member. Thus, in a simple manner, the covering is positively secured in the frame.

Abstract: The invention comprises a road cutting equipment for cutting grooves, or slots in road surfaces and comprises an apparatus attached to an end of a vehicle. When the apparatus is not in use it is rasied clear of the road surface so that the vehicle can travel over the road surface in normal fashion. When the equipment is to be used it is lowered relative to the vehicle and the vehicle is supported by the equipment on legs of which the lower ends have rollers. At the same time a cutter disc or drum is driven and penetrates the road surface. The equipment in this condition is driven forward, by a drive means which directly drives one or more of said rollers.

Abstract: The paving stone set consists of stones 11-16 each with six lateral boundary surfaces 1-6, 17-22. Four of these boundary surfaces 1 and 4; 3 and 5; 18 and 21; 19 and 22 are parallel to one of the other of the four surfaces, while the remaining two surfaces 2 and 6; 17 and 20 define planes which intersect at an acute angle. On the straight edges, the stones 11-13 are laid alternatingly. A joint pattern is created with expansion joints, which do not stand vertically to the support joints. The expansion joints are formed from two wedges directed opposite to one another, and therefore have an effect which is irregular in comparison with the support joints. The slotted boundary surfaces 2, 6 make it possible to lay the stones 11-13 according to the sloping angles selected in curves with small radii chosen as desired, whereby the wedge-shaped joints close gradually. The stones 14-16 serve as a supplementary curve set, and make possible the laying of Roman arrow patterns, as well as an Archimedean spiral.

Abstract: A bridge and a method of constructing the bridge over water. A bridge span is positioned longitudinally in portion through a slot in a bridge pier; then the span is moved laterally through the slot to a position in the center of the pier at a low level. Then the span is hoisted up to its correct position. The hoisting step may be preceded by or may include placing jacks under the span and directly above the bottom of the pier and then employing the jacks in the hoisting step. The bridge or bridge segment comprises a pair of pier portions with a span-accepting slot between them, each pier portion comprising an underwater footing and a vertical pier portion resting on, secured to, and rising from the footing to a deck-support platform.

Abstract: An improved grass mower and attachment which employs a sling for holding a disposable bag is disclosed. The sling is open to one side so that full bags can be unloaded without lifting. The sling is mounted to a frame which receives the margin of the bag and this frame is mounted so that it can both pivot downward (when unlatched) and slide rearward relative to a housing from which clippings are delivered to the bag during grass cutting. When the bag is desired to be unloaded, the frame is unlatched and the sling, which is otherwise held above the ground, pivots its open side down to the ground. The housing can slide from over the frame by advancing the mower. The filled bag can be then tied and rolled out of the sling onto the ground without lifting it. A new bag can be fitted to the frame, inside the sling, and the lightweight frame, sling and empty bag returned and relatched under the housing and the mower used to fill the new bag.

Abstract: In a lawnmower including a housing and wheels for supporting the housing from a ground surface, a wheel height adjusting mechanism including a crank arm associated with each wheel, the crank arms being coupled together for the conjoint movement thereof, the coupling including a shaft mounted from the housing for rotation about its axis, the improvement comprising a gear secured to the shaft for rotation therewith, a plunger supported from the housing so as to be movable between a first position interfering with the gear means and a second non-interfering position, and a spring biasing the plunger to the first position. The plunger may be trigger operated, and the trigger associated with a deck mounted handle. A safety flap may be mounted from the shaft to maintain a relatively constant height from the ground as the wheel height is adjusted.

Abstract: An adjustable manhole top which can be readily raised up or down in minutes to correct problems when the ground around it heaves. A cylindrical sleeve with a plurality of spaced elongated shoulders extending longitudinally along an internal surface thereof, is adjustably seated about upwardly extending projections from a support rim. A lock, removably supported on the support rim, is provided with a height adjustment mechanism to support a corresponding shoulder on the sleeve, to secure the sleeve at a desired height.

Abstract: An improved ripper using a hydraulic hammer with a rotating long service life hammer tool is provided. The tool is cylindrical with a large cylindrical upper portion and a central portion of reduced diameter. The tool is retained in the hammer by means of a pin passing through the tool cavity of the hammer housing which prevents passage of the large upper portion.

Abstract: To divert sufficient fluid flow through an unsealed bearing section of a downhole drilling motor, a flow control apparatus is provided for insertion between the power section of the motor and the bottom of a drill bit which is to be turned by the motor. The flow control apparatus includes a variable flow channel having a selectable effective cross-sectional area preferably embodied by a valve. A selected effective cross-sectional area is chosen by a control mechanism, such as a snap ring or a spring used to control the position of a valve member of the valve in response to different flow rates of fluid pumped through the valve depending upon whether the drill bit is on-bottom or off-bottom. In one embodiment the apparatus is incorporated within the interior of a drill bit which has angled flow channels to direct flushing fluid flow to side wall locations where reaming occurs. Flow through these outlets is controlled by positioning of the valve member.

Abstract: A polymer plastic contraction-expansion joint element for the aggregate decking areas of a swimming pool. The element when used as a contraction joint is comprised of an elongated generally hollow body adapted for burial in the aggregate just below grade level. The body is formed of a bottom wall and parallel spaced apart upright sidewalls terminating at their upper distal ends in an open pocket including longitudinal protuberances oppositely extending along the inner face of the sidewalls. Adapted to overlie the body pocket at grade level in a removable mounting relation thereto is an imperforate polymer plastic cover having elongated skirts downwardly depending from the opposite longitudinal side edges thereof. The skirts are insertable between the body protuberances in a springlike interfit enabling the cover to be removed and replaced as appropriate.

Abstract: Method and apparatus are provided for resurfacing recreational (e.g., tennis) courts and other surfaces. The apparatus includes self-contained drive system including drive wheels mounted on an elongated frame structure, and additionally supported for rolling movement on a plurality of casters. The apparatus is provided with flexible blade and brush elements for spreading and smoothing court resurfacing material uniformly across the surface. In a forward resurfacing direction, flexible squeegee-type blades, with or without associated brushes, engage the resurfacing material ahead of the device, while flexible brush elements engage the resurfacing material behind the device to erase tracks caused by the drive wheels and casters, and to effect final smoothing and texturing of the resurfacing material. The drive wheels may be moved into and out of ground engaging contact, and a steering device provides for lifting one or the other of the drive wheels out of ground engaging contact.

Abstract: This invention discloses an adjustable support securable to metal decking to support a metal keyway form. The adjustable support can be used to establish keyway in concrete poured above ground level, particularly on metal decking. This method of producing a keyway in concrete on metal decking is a vast improvement over previous art and provides a secure, easy, inexpensive method of producing the keyway.

Abstract: A grinding assembly for grinding asphaltic pavement which attaches to a vehicle frame and includes a grinder and a grinder blade attached to the rear of the grinder. The lower edge of the blade extends down to a bottom of the grinder so as to contact unground pavement during operation. A brace assembly is affixed to the grinder and an adjustment brace coupling is affixed to the vehicle frame and is connectable to the brace assembly. The brace coupling is adjustable to pivot the grinder to change the elevation of the grinding surface relative to the lower edge of the blade.

Abstract: A variable force tree shaker is disclosed which includes a non-rotatable housing having a two-piece shaft journaled therein. A fixed weight is rigidly connected to the shaft and an adjustable weight is pivotally connected to the shaft. At least one hydraulic cylinder is formed in the fixed weight and receives a piston which is connected to the adjustable weight by a piston rod. While the shaft is driven, an hydraulic controller directs hydraulic fluid into said at least one piston which moves the adjustable weight between a balanced position diametrically opposed to the fixed weight providing no shaking forces to the shaft, and a plurality of unbalanced positions imparting shaking forces of different intensities to the shaft.

Abstract: The invention relates to a mowing device applicable to any type of front cutting or non-front cutting mowing machine, power mower or mower driven by a tractor or other vehicle, comprising a support bar preferably rigidly fixed to the mowing machine frame, and with which there are associated, in a fixed position, guide means for a comb and for a cutting blade which overlies the comb, these latter oscillating in opposite directions longitudinally to said support bar. The comb is provided with teeth which extend forwards and are provided with tangs directed rearwardly and upwardly. Drive means are provided to cause the blade and comb to oscillate in phase opposition so as to dynamically compensate the device wholly or partly, the travel strokes of the blade and comb being preferably inversely proportional to their respective masses, the mass ratio of comb to blade being preferably between 1.5 and 3.