Abstract: A twin cylinder pump for viscous materials such as concrete, having a guide for a cutting ring producing a sealing effect on the cylinder and a seat for supporting a loaded spring ring of elastic material of rubber or the like, is so designed that the ring is acted upon by the pressure of the feed taking effect in the ring-like gap, open as far as supporting face or seat of the spring, between the cutting ring and the valve member. Furthermore there is a guiding and constraining means for the ring taking effect thereon between the radial faces against which it is rested.

Abstract: The valve has a shutter mechanism which is movable within a housing and is provided at one end with at least one inlet which is movable across one or more housing openings and at the opposite end with an outlet surrounded by a sealed contact joint which is movable across a delivery pipe opening in the housing. This sealed contact joint surrounds the delivery pipe opening in the housing and contacts either the inside wall of the housing or a face plate arranged on the inside wall of the housing in all intermediate and final positions of the shutter mechanism. With the aim of reducing wear and producing a permanent seal, the sealed contact joint is in the form of a compressible sealing ring with a slotted or kidney-shaped cross-section which serves to wipe the flat and smooth face plate or inside wall of the housing.

Abstract: A two-cylinder pump for heavy flowable materials, such as concrete, comprising a shutter mechanism which is pivotable across an apertured face plate, the shutter mechanism being sealed against the face plate by means of a cutting ring which is axially movable relatively to the shutter mechanism and is supported thereon with its rear side engaging a rectangular-section flexible rubber ring, whereby the cutting ring is urged resiliently against the face plate, means for locating the cutting ring, along a portion of its length, on the shutter mechanism, a seating for the flexible ring on the cutting ring which includes an annular extension which partly overlaps the longer cross-sectional side of the flexible ring in the axial direction, a seating for the flexible ring on the shutter mechanism which includes an annular extension which partly overlaps the longer cross-sectional side of the flexible ring in the axial direction, said annular extensions partly overlapping the ring from opposite sides thereof so that

Abstract: A two-cylinder viscous material pump has parallel axis, conveying cylinders mounted in a frame work. The conveying cylinders alternately suck in the viscous material through an inlet valve housing from a reservoir and press it out, in the following stroke, through an outlet valve housing. In each valve housing, a pressure controlled valve with a valve drive cylinder is provided for each conveying cylinder, and the inlet and outlet valve drive cylinders are arranged axis parallel. The conveying cylinders as well as the inlet and outlet valve drive cylinders are arranged one above the other and the reservoir (41) is mounted laterally on the inlet valve housing with a suction bend.

Abstract: A trench hoe-type excavator carries a digging bucket at the end of a digging device. The bucket and digging device are capable of being driven so as to maintain a set cutting angle. An indicating apparatus arranged in the field of view of the excavator operator allows the operator to check the position of the digging device to determine the direction in which the bucket must be guided in order to obtain the desired inclination and direction of the ditch floor. The indicator apparatus includes a laser transmitter and a transparent target. The transparent target is carried by the digging device and has a first surface facing the bucket operator and a second surface which is arranged to receive the laser beam from the laser transmitter. The laser transmitter is arranged on the opposite side of the target from the excavator operator, so that the position of the end point of the laser beam on the target can be observed, parallax-free, by the excavator operator during the entire digging operation.

Abstract: A viscous material pump, in particular for the conveyance of concrete through a housing (3) of a switch tube (2) has a swivel body (26) fastened on an axially supported pivot shaft (44). The swivel body alternately connects a discharge opening (25) mounted in a housing wall with two inlet openings (6, 7) arranged in another housing wall. The centers of the inlet and outlet openings, respectively, are arranged in radial displacement from the shaft axis (35). The displacement of the inlet openings (6, 7) and the discharge opening (25) from the shaft axis (35) differs and is so selected that the displacement (R.sub.1) of the inlet openings (6, 7) is larger than the displacement (R.sub.2) of the discharge opening (25).

Abstract: A piping valve for conduits conveying pressurized viscous material, such as concrete, provides a means for introducing a wiper into the conduit for cleaning purposes. The piping valve has a reciprocally displaceable part with a transmission pipe and a pipe chamber containing the wiper. The reciprocally displaceable part may be moved between a first position in which it is aligned with the conduit and a second position in which it receives the wiper for passage through the conduit.

Abstract: A valve structure for a viscous material pump having a material reservoir, a pair of alternately operable material conveying cylinders, discharge conduit means, and a valve control means coupled to the valve structure and to the material conveying cylinders. The valve structure has a pair of movable swivel pipes extending between the conveying cylinders and the discharge conduit means. Each of the swivel pipes has an opening movable over one of the conveying cylinders to receive the contents discharged therefrom and a plate movable over said one conveying cylinder to block same.

Abstract: A mixer for viscous material has a plurality of rotating knife impellers which coact with stationary breaking knives in a cylindrical housing. The cylindrical housing has a converging portion containing guide ribs, stationary knives, and guide paddles. The shaft, in the converging portion, mounts helical ribbon segments and thrust paddles.

Abstract: An apparatus for distributing concrete, especially in the shuttering of gallery linings in mining and tunnel workings, comprises a transportable distribution mast carrying an articulated conduit for conveying concrete which is pivoted on a column which can rotate around its axis. The mast comprises a swivel extension forming the end section thereof, and a main boom which connects the column to the swivel extension, the swivel extension being foldable from above onto the main boom. The main boom is divided into several mast sections joined together by power-operated pivotal connections so that the mast is articulatable in a swivel plane containing the column axis, the range of relative pivotal movement between the mast sections being such that the main boom may be extended upwardly and forwardly from the folded position of the mast sections, with the swivel extension in its folded position, the power-operated pivotal connections of the main boom being disposed below the folded swivel extension.

Abstract: An excavating machine has an indicator (60, 64) showing the position of the boom and dipper stick mounted back hoe (29) to the machine operator. A guide rod (33) is coupled to the hoe and to a swivel joint (34) on the machine to drive the indicator. The angle of the hoe may be shown by an additional indicator (83, 84).

Abstract: A multicylinder piston pump for pumping viscous liquids of varying composition with each cylinder having an extendible tubular piston intake valve and discharge valve is disclosed. The extendible tubular piston valves have a tubular piston slidably mounted in a cylindrical passage of a housing mounted adjacent to each cylinder. The tubular piston has an inner bore into which an inner piston is slidably mounted therein. The inner piston is connected to a piston rod which is connected to the housing. Hydraulic oil is used to extend each tubular piston valve so as to control the intake and discharge of fluid into the piston pump.

Abstract: In a double-cylinder pump for conveying cement, a distribution pipe is pivotally driven into alignment with each of the cylinders in turn. A wearing ring, which provides a seal between the end of the pipe and the cylinders, is mounted so as to be movable with respect to the end of the pipe so as to be able to assimilate wear.