Abstract:
An AC voltage controller has two transistors which can be positioned between two AC voltage terminals in series with a load. The two transistors are connected in series in such a way that their respective source terminals are connected to one another. The AC voltage controller also contains a signal generator for generating a switching signal for actuating the two transistors, a buffer which is connected downstream of the signal generator and which is set by the signal generator in order to actuate the two transistors. An actuation circuit or driver circuit is connected downstream of the buffer, for the purpose of actuating the two transistors in accordance with the set state of the buffer. A current-limiting circuit is provided for limiting or switching off the current through the two transistors in the case of an excessively large current through the load.
Abstract:
After extrusion, cutting, and tilting 90.degree. alternate green bricks are rotated 180.degree. about a vertical axis to form brick pairs with the back (unfinished) sides of both bricks facing each other. These reoriented brick pairs are then gripped and stacked. Conventional grippers, such as a vacuum gripper, may be used to grip only the backs of each brick in the pair. In this way, all of the finished faces of the stacked bricks avoid damage while simultaneously being more uniformly exposed to the kiln drying and firing atmosphere and thus may achieve a more uniform appearance. No special tools are required to handle irregular or specially designed brick faces because the gripper grips only the back of each brick pair.
Abstract:
The invention is based on a fuel injection pump in which to supply a very rapid pressure rise in the interior of a fuel injection pump, a pressure valve controlling this pressure is modified such that upon cold starting of the engine, the pressure valve closes a bypass line at the feed pump and thus delivers all the fuel to the fuel injection pump. The closure is effected as a function of rpm and accordingly pressure, and also as a function of the engine operating temperature; in the fuel injection pump according to the invention, the rpm- and pressure-dependent diversion is performed by the adjusting piston of an injection adjuster. Thus, compared with the known cold-starting accelerating devices, one additional pressure limiting valve can be eliminated.
Abstract:
A process for hydrogenating mediators with the aid of surfactant-modified metal catalysts, and catalysts which can be used for this purpose, are described.
Abstract:
Apparatus for severing bags from a two-ply web of thermoplastic material. The apparatus includes web guide rollers defining a nip, and a plurality of peripheral grooves in the guide rollers in which upper and lower air directing tubes are positioned to guide a web as it passes downstream of the feed rollers. A continuously transversely moving severing knife is provided downstream of the feed rollers and below the plane defined by the moving web. A pair of welding jaws are provided adjacent the cutting knife to grip the web in a plane below the web movement plane to weld the plies of the web together and to deflect the web into position for providing a transverse cut therein by means of the severing knife. A pivot lever is provided to pivot downstream ends of the lower air directing tubes in a downward direction to prevent interference between the downwardly deflected web and the downstream ends of the air directing tubes. A set of clamping jaws is provided on the opposite side of the severing knife from the welding jaws in order to securely hold the web during the cutting operation.
Abstract:
An appliance with a hazardous device contains a first controller controlled by a first control element which, in turn, is controlled by a second controller by use of a first switching element. An electrically controllable protection device is provided and is controlled by a second control element, it is possible to deactivate the protection device. A storage capacitor is provided between the first and the second control element and supplies the second control element with energy for a control pulse and is charged by the first control element when the first controller is switched off and is discharged by the first switching element when the first controller is switched on. This circuit generates a safe control circuit. In the event of a possible hazardous state, either the first controller is no longer supplied with energy or the protection device cannot be deactivated, and so danger to a user is precluded.
Abstract:
A method and apparatus for maintaining a glue applicator unit ready for operation after short or long term stoppages of a gluing operation. During short term stoppages, the applicator unit is pivoted away from the workpieces to which the glue is to be applied to a first rest position at which the nozzles are brought into tight engagement with a sealing means that includes a yieldable surface to surround and overlie the nozzles to provide an airtight seal. During long-term stoppages the glue applicators are pivoted beyond the first rest position to a second rest position at which the nozzles are in communication with a drain channel and purge fluid is sent through the applicator to pass through the nozzles and carry the glue and purge fluid to a collecting container, so that the nozzles are clear for subsequent start-up of the glue-applying operation.
Abstract:
An injection device is proposed for internal combustion engines whose vane cell pump has two channels 23, 22. Each channel begins at the end portion of the compression recess 21 and discharges into the congruent openings 24, 25 of the support ring 17 and of the receiving ring 16, respectively. These openings are embodied as grooves and are disposed near the rotary wall 28 of the housing 10 of the injection device.