Abstract: A swirl jet nozzle as a hydraulic work tool is to be capable of operating reliably as a structurally simple tool, with smooth outer surfaces as far as possible, requiring neither bearings nor seals, so that it is also suitable for cleaning clogged, narrow tubular parts, in particular pipes, with a high-pressure medium and for drilling holes in soft materials. This is achieved by a sleeve-shaped rotor (1), arranged directly above a tapered neck (5) of a stator (2), being provided, which is supported on the stator side on a face (7) of an extended region (8) of the stator (2), preferably via a washer (6) of plastic or the like pushed over the neck (5) of the stator (2), and is axially secured by means of at least one pin (11) engaging tangentially into a circular groove (9) in the neck (5) and borne in a cross bore (10) in the rotor (1).

Abstract: A device for regulating a diesel motor driven feed pump which includes an injection pump associated with the diesel motor to control its operating speed, comprises a load, a variable pressure resistance connected by a feed line in series in series to the feed pump and a sump for the feed pump connected to the pressure resistance. In addition a control circuit is connected to the feed line and it includes a pressure scale portion and a limiting device portion each of which includes a respective pressure scale cylinder and limiting device cylinder portion for their respective coaxially arranged pressure scale piston and limiting piston slidable therein. A differential manometer is connected between the pressure scale portion and the limiting portion and it is admitted with the flow medium of respective differential pressures of the associated cylinders of these portions.

Abstract: A sliding surface packing for use in pumps and particularly high-pressure pumps between spaced apart pair of prop rings and a pump plunger and a pump cylinder wall comprises a plurality of packing rings arranged between the prop rings. At least one of the packing rings comprises a rigid high-pressure ring and at least one packing ring comprises a flexible leakage ring and at least one packing ring comprises a high-pressure ring. A plurality of self-lubricating packing rings form guide rings embedding the leakage ring between adjacent ones of said self-lubricating guides forming a pack of laminations.

Abstract: A conduit-cleaning assembly has a swivel coupling connected between a high-pressure hose and a conduit-cleaning nozzle. This coupling has an outer end tube connected to the hose, an intermediate outer tube threaded with the outer end tube, and an inner tube connected to the nozzle and forming with the outer tubes an axis-defining passage for liquid to flow into the nozzle from the hose. This inner tube is partially received in the outer tubes and has an inner-tube end whose outer edge engages an annular seal whose outer periphery is locked to the outer end tube. A bearing is provided between the inner tube and the intermediate tube to allow the parts to rotate relative to each other. The annular seal has a pair of opposite pressure-equalizing surfaces both exposed to the full pressure inside the swivel.

Abstract: A high-pressure pump has a housing whose cylindrical chamber is subdivided by a piston into a fixed-volume compartment and a variable-volume compartment. An orbital crank is connected via a connecting rod to this piston to reciprocate it in the housing and thereby cyclically increase and decrease the volume of the variable-volume compartment. This variable-volume compartment is connected via a downstream conduit and a checkvalve to a supply of liquid lubricant, and to an upstream conduit and an upstream checkvalve both to the fixed-volume compartment and to the joints or bearings at the end of the connecting rod.

Abstract: A high-pressure liquid-jet gun has a pistol-type housing provided with a valve having an actuation member displaceable between a closed position and an open position to release liquid from an end of the housing. A safety lever is displaceable on the housing between a safety position relatively far from the barrel of the housing and a use position lying against this barrel. A spring urges this safety lever into the safety position. A trigger is pivoted on the safety lever and has a formation which is engageable only in the use position of the safety lever with the actuation member. This trigger can be displaced in the use position of the safety lever between an advanced position with the formation engageable with the actuation member but with this actuation member in the closed position, and a drawn-back position with the formation pressing the actuation member of the valve into the open position.

Abstract: The housing of a pressure-relief valve has an inlet port forming an inlet valve seat, an outlet port, a valve chamber between the ports, and an abutment in the valve chamber. A valve body in this chamber has an inlet end engageable in the inlet valve seat and an outlet end, and is displaceable in the housing between a closed position with its inlet end seated in and blocking the inlet valve seat and an open position engaging the abutment and with its inlet end spaced from the inlet valve seat. A pilot piston in the valve chamber has a throughgoing passage opening at one end at the outlet port and forming at its opposite end an outlet valve seat engageable with the outlet end of the valve body. This piston is itself displaceable in the housing between an open position with its outlet valve seat spaced from the outlet end of the valve body in either position thereof and a closed position with its outlet valve seat engaging and blocked by the outlet end. A spring urges this piston into the closed position.

Abstract: A surface-cleaning apparatus, especially for street cleaning and the cleaning of industrial surfaces, comprises an array of high-pressure water nozzles surrounding a pick-up nozzle whose open end is formed with a flow accelerating hood, the pressure nozzle surrounding this hood being constituted as drive nozzles whose water sprays are trained beneath the collecting nozzle. The collecting nozzle is connected to a suction source which draws the dirty water upwardly after the water is reflected from the surface to be cleaned. The device is mounted upon a vehicle or is displaceable by a vehicle.

Abstract: A shutoff valve for high and maximum pressures comprises a housing with an inlet passage communicating with a discharge passage and having a valve seat therebetween which is closable by a differential piston having one face which is seatable on the valve and an opposite face in a first control chamber. The first control chamber is connectable through a first control valve to a bypass which extends to the discharge passage. In addition a second control chamber is located in the bypass passage and it is regulated by a separate second control valve. A separate control member such as a pivotal lever is associated with each control valve and each must be separately operable in order to permit movement of the differential piston off the valve seat to open the flow passage.

Abstract: A shutoff-valve, for high and highest pressures (i.e. pressure in the range of hundreds to thousands of kp/cm.sup.2) especially for a high-pressure spray gun, has a common pressure chamber for a differential piston driven by the pressure medium (e.g. liquid or gas) and a control piston of either ball-, cone-. cylinder-, plate-, or similar shape. The control piston cooperates with a control pin displaced by an operating lever. The shutoff-valve, working on a largely hydraulic basis by creating underpressure, is brought into closing position by means of a bypass channel for controlled flow of the medium and is opened by displacement of the operating lever.

Abstract: An apparatus for treating a surface with a liquid has a support displaceable over the surface and carrying a spray beam itself provided with a plurality of nozzles directed at the surface. A diffuser surrounds a plurality of the nozzles and has a deflector for diverting the streams of liquid emitted by the nozzles so that these streams flow in a direction generally parallel to the surface being treated. Rollers maintain the front face of the deflector a predetermined distance from the surface being treated. The spray beam may be in two sections which are oppositely reciprocated to increase the treatment effect.

Abstract: A vehicle, contains a washing and vacuuming machine for cleaning streets and similar surfaces, which includes a wheeled body containing a tank which holds cleaning water or a similar liquid, and a pump for directing the water through a spray nozzle which is positioned in a hood located below the body adjacent the ground. A vacuuming suction shoe is located within the hood forwardly in the travel direction in respect to the nozzle so that the nozzle is aimed forwardly toward the intake of the suction shoe which is spaced upwardly from a perimetric skirt element of the hood. The hood is advantageously carried on a separate carriage which is biased by a suitable washing arrangement so that it moves inwardly toward one side of the vehicle, for example, toward the curb side. The carriage is adapted to have guide wheels which engage along the curb so that the vacuuming device and spray nozzle will be directed in a location adjacent the curb to effect the cleaning thereof.