Abstract: The device permits locking of a control knob which can rotate around a cylindrical support and includes a lateral face with at least one first locking boss and a lateral face of a ring which has at least one second locking boss. The ring is movable in translation according to the axis between a locked position of the knob, in which the ring is prevented from rotating around the axis when the first and second bosses are engaged, and between a released position in which the first and second bosses are decoupled.

Abstract: In a hydraulically controlled diaphragm pump for high pressures, the diaphragm situated between the hydraulic control chamber and the working chamber is composite and comprises two thin metal diaphragms having between them an intermediate diaphragm that is thick, is made of synthetic material, has high crushing strength, and is in the form of an elastically deformable vault whose concave side faces towards the working chamber.

Abstract: Moving equipment for applying reciprocating drive to the diaphragm of a mechanically actuated diaphragm pump of adjustable stroke, the moving equipment comprising a slider slidably mounted in a fixed guide co-operating at one of its ends with an eccentric drive device whose eccentricity defines the maximum amplitude of the stroke of the slider in the guide, and coupled at its other end to the membrane.

Abstract: A system for controlling the throughput of a metering pump, the pump including a pumping member (8) driven by a transmission member (4) for converting rotary motion of a reversible drive motor (1) into reciprocating motion of the pumping member, the system comprising means for adjusting the amplitude of the reciprocating motion and means for adjusting the period of said motion.

Abstract: The invention relates to an improvement in variable capacity diaphragm pumps. According to the invention, the piston is driven by a cam fast with the wheel of a speed reducing gear pair, the eccentric/wheel assembly rotating idly on a fixzed shaft of which the axis is perpendicular to the axis of the piston, the piston terminating in a U-shaped shank of which the wings are perpendicular to the axis of the piston and spaced apart by a length slightly greater than the diameter of the eccentric, and of which the base is perpendicular to said fixed shaft and is provided with a longitudinal groove parallel to the axis of the piston which is traversed by the fixed shaft, the eccentric being housed between the wings of the shank. The invention is more particularly applicable to the manufacture of diaphagm pumps.

Abstract: The groove (13) for detecting the presence of a fluid between the membranes (1, 2) and indicating that one or other of them has broken, is profiled so as to be bullet-shaped, thereby preventing the membranes from being extruded into the groove under the effect of pumping pressure.

Abstract: A pump in accordance with the invention has moving equipment (32) driven by a reversible synchronous motor (42) whose windings (44, 45) are connected to a power source by means of optocoupled triacs (48, 49) which, under microprocessor control, are used to adjust the flow rate of the pump by acting on its admission period (by powering the windings in one direction) and on the pumping cycle time (by varying the period for which the pump is unpowered in each cycle).

Abstract: The present invention relates to a hydraulically controlled diaphragm pump, comprising an intermediate chamber filled with fluid, and a re-filling conduit for said chamber.According to the invention, means are provided for controlling the closing and the opening of the said conduit, which means are constituted by a valve cooperating with a fixed seat through which the said re-filling conduit reaches into the said intermediate chamber. Said valve is mounted for sliding on a rod, which rod is also mounted for sliding longitudinally inside a fixed support in the said intermediate chamber and traverses the said seat, a shoulder of the said rod forming means for moving the said valve and holding it on its seat, an actuating surface of the said rod, opposite the said shoulder, forming the rear of the diaphragm and a spring being coupled between the said support and the said actuating surface for closing the said valve.The invention finds an application in the field of mechanical engineering.

Abstract: In a reciprocating pump, notably a metering pump, of the reciprocating type in which the pumping member, diaphragm or piston, is actuated by means of a slide block responsive to a rotating eccentric member, a ball is interposed between an adjustment screw controlling the length of the slide block stroke and the slide block. For this purpose, the ball engages an inclined surface formed in a hollow of the slide block. Preferably, the screw is magnetized and constantly attracts the ball to avoid movements of the ball in relation to the slide block and therefore any premature wear and tear of these members. The inclined surface may have a shape matching that of the ball.

Abstract: Apparatus for feeding pulverulent materials comprising a hopper with an upper vibrating portion mounted on a lower portion in which a screw equipped with a recycling arm and an associated stirring device feeds the pulverulent material at a desired rate through a discharge conduit mounted at the base of the hopper.