Abstract: The invention is directed to a dental handpiece 1 comprising a grip sleeve 2 having at least one cordlike light guide 18 in the area of the handpiece head part 4 which passes out of the latter in the direction of the tooth treatment tool 5 and accordingly extends in its entirety within the grip sleeve 2 and is connected at the rear end to a light source 14. In addition, a detachable connecting piece 10 is provided for the connection at the end member 29 of a supply tube for the supply media of the handpiece, the connecting piece 10 being arranged so as to be freely rotatable relative to the grip sleeve 2, wherein the connecting piece 10 is provided with media throughpass ducts 22, 23, 24 which open into it and pass through it and which are connectable with media lines of the grip sleeve 2 leading to the use positions of the handpiece.

Abstract: A zoom lens having at least 4 components of which the 1st component counting from the front is of positive refractive power and the 2nd and 3rd components are of negative refractive power, wherein the aforesaid 1st, 2nd and 3rd components are made movable for moving in respective loci, which are different from each other, to effect zooming.

Abstract: An external shaft rotary piston machine wherein pistons of a piston rotor run in engagement with a cavity of a circular cylindrical sealing rotor during a particular relative rotational position of the rotors, the cavity being substantially larger than necessary for passage of the pistons in order to avoid flow losses due to seal wedging flow and compression. In order to avoid overflow from the high pressure side to the low pressure side of the machine through the sealing rotor while the pistons move in the sealing rotor through the space defined by the cavity, a sealing effect is created by a leading edge and a trailing edge portion of the opening of the cavity of the sealing rotor moving along a leading and a trailing side surface of the pistons. This is effected kinematically due to the fact that the trailing edge of the cavity opening is displaced radially inwardly and that an edge portion extends from the trailing edge convexly relative to the peripheral surface of the sealing rotor.

Abstract: A mechanical mounting for a lens system having a focusing or a zoom component. A motor for driving a lens holder for the component includes a field coil of hollow cylindrical shape drivingly connected to the lens holder for the component and rotatably fitted on a circular array of field magnet elements which are secured to a tubular body. The holder is moved axially within the tubular body by the motor.

Abstract: In the removal of the overburden prior to surface mining of minerals in an elongated pit, one or more first excavating machines remove the overburden along one elongated part of the pit and direct the removed material via a cross-pit transporter across the pit where it is deposited outwardly from and along the opposite side, called the dump side. At least one other excavating machine travels along the remaining elongated part of the pit at a level not higher than the level of the cross-pit transporter and removes the overburden to the same dump side of the pit. The excavating machines moving along the elongated part of the pit operate independently of one another. When the cross-pit transporter and the second excavating machine operating in the remaining elongated part of the pit on the same level, meet while moving in opposite directions, the second excavating machine moves across the pit out of the path of the cross-pit transporter and the transporter is moved past the second excavating machine.

Abstract: An adjustable formwork for forming the corner surfaces of concrete structural members includes a first and a second formwork unit. Each formwork unit extends transversely of the other and has a surface which forms one of the concrete surfaces of the concrete structural members and these surfaces define a corner junction line about which the formwork units can be pivotally adjusted relative to one another. One of the formwork units is provided with a circular-arc shaped guide slot and the other has a pair of spaced guide pins secured to it with the pins being movably guided in the slot. The center point of the arc of the slot is located on the corner junction line. The interengagement of the pins with the slot affords a link type guidance between the formwork units. As a result, forces are transmitted at the corner junction line only in the assembly state so that the line lies practically in the plane of the formwork surface which define the concrete surfaces.

Abstract: A device for driving fastening elements, such as nails, staples and the like, includes a magazine extending transversely from a driving unit. A follower is located within the magazine for supplying fastening elements to the driving unit. For filling the magazine with fastening elements, the follower can be secured in a loading position. The follower is secured by a stop pivotally attached to the follower which engages an abutment on the magazine. The follower is released from the loading position by an actuating member movably mounted on the magazine so that it can contact an engagement part on the follower and pivot the stop out of engagement with the abutment.

Abstract: The friction disc clutch for a motor vehicle driven by an internal combustion engine comprises a flywheel which is driven through a rotationally elastic element by the crankshaft of the internal combustion engine. The mass-spring system of the drive path of the clutch is so dimensioned that natural vibrations occur in or below the idling rotation rate range of the internal combustion engine. The rotationally elastic element can be bridged over for rotation rates in the range of and below the idling rotation rate in order to prevent resonance effects in idling and in the starting of the internal combustion engine. The bridge-over clutch can be formed by a pinion of the starter motor. Alternatively, centrifugal clutches can be used.

Abstract: A molded tapping fitting is made up of a saddle piece to be secured to a pipeline to be tapped, a tapping connection member and a branch connection line attached to the saddle piece. In combination, the saddle piece, the tapping connection member and the branch connection line form a chamber opening through the saddle piece into the pipeline. The interior of the chamber is shaped to facilitate the deflection of flow from the pipeline into the branch connection line.

Abstract: A method for bonding Si.sub.3 N.sub.4 or SiC ceramics with metals which comprises the steps of depositing, on the ceramic material, an insert material consisting of a mixture of at least one metal selected from the group consisting of Ni and Cu and at least one member selected from the group consisting of metal oxides, nitrides and carbides by ion plating or spary coating, subjecting the deposited insert material to thermal reaction treatment to permit metallurgical bond between the insert material and the ceramic material, and bonding a metal member to the surface of the insert material by brazing with a brazing material whose melting point is lower than the insert material or by diffusion welding at a temperature lower than a melting point of the insert material.

Abstract: The disclosed flash device is of the kind that incorporates an integrated processing circuit requiring a stable voltage, but one and the same battery supplies both a booster circuit and the processing circuit. The device avoids the drop in voltage to the processing circuit when the booster circuit draws current after a flash by means of a detector circuit that detects the flash or the operation of the booster circuit. A switching circuit responds to the output of the detector circuit and supplies the charge on a back-up capacitor to the integrated processing circuit. Thus, in the event of a flash, the processing circuit which is normally operated by power from the battery is protected from a supply voltage drop by the supply of a voltage from the back-up capacitor.

Abstract: In the distillation of fresh water from sea water, the sea water is passed ownwardly in a falling film evaporator through a multiplicity of vertical tube evaporator (VTE) stages and multiple stage flash (MSF) evaporators. After the sea water passes through the first VTE stage where it forms a liquid component and a steam component, the liquid component is distributed evenly into the next VTE stage while the steam component enters an adjoining MSF stage. Condensed fresh water flows downwardly from one MSF stage to the next and experiences flash evaporation. The sea water or brine component and the fresh water distillate flow downwardly through the VTE and MSF stages so that the brine component can be removed from the final VTE stage and the fresh water distillate from the final MSF stage.

Abstract: In determine and ascertain the physical state of birds and animals in a livestock raising establishment, the batches of such creatures are weighed at certain time intervals, the information on the weight of a bird or an animal is signalled to a computer and is stored in the memory of the latter, the average weight of a number of birds or animals is calculated which gives an indication of the physical state of the respective creatures. To practice the method a weighing apparatus is used including a weighing platform, a load cell attached to the said platform and being capable of converting the pressure of the load on the platform into an electric signal, and an electronic interface adapted to receive the signal and transmit it to a computer with wiring connecting the constituents of the system.

Abstract: A method of vaporizing additives in a metal melt. The method is carried out in a vessel which has a chamber in which at least one additive is placed. The geometric configuration of the chamber and the total cross-sectional area of the openings are adjusted in relation to the amount T of metal melt, so that a vaporization t=68.times.T.sup.0.22 .times.A is obtained. This method has the advantage that parameters, such as, residual magnesium content can be accurately reproduced.

Abstract: A zoom lens mounting capable of focusing beyond the usual range of object distances towards close ups in a particular region of the zooming range has a control member which changes its position depending upon the relative position of a focusing actuator to a zoom control cam member or vice versa, wherein the aforesaid focusing actuator and the aforesaid cam member are each provided with an area subject to constraint with the aforesaid control member and an area not subject to the constraint.

Abstract: An automatic focusing device having a light projecting device, a light receiving device arranged to detect a reflection light quantity reflected by an object to be photographed as a result of light projection by the light projecting device and a distance measuring device arranged to measure a distance to the object by the reflection light quantity received by the light receiving device is capable of adequately performing a focusing operation even in cases where the reflection light quantity is at a level too low for the distance measuring device to give any result of distance measurement.

Abstract: For introducing additives, such as inoculating agents, into a metal bath, the additive is held in a supply container. A slide device carries measured amounts of the additive from the supply container to an immersion pipe extending downwardly into a metal bath located in a vessel. A flow of gas is provided into the immersion pipe adjacent the point where the additive is introduced into the pipe. The gas carries the additive downwardly through the immersion pipe for mixture into the metal bath. The additive can be supplied continuously or in intermittent portions to the immersion pipe. The additive is introduced below the surface of the metal bath in accurately measured amounts in a safe reproducible manner.

Abstract: An automatic exposure control camera is arranged to permit selection of a stop-down aperture priority mode in which an actually stopped down aperture has priority when a specific lens is mounted on the camera.