摘要:
Circuit arrangement for an inductive load with a rotor and at least one winding, a DC-voltage intermediate circuit and at least one switchable semiconductor rectifier of a power stage connected to the winding for passing a current therethrough, and a current regulator subject to hysteresis for regulating the current, includes control electronics connected to the current regulator for prescribing the hysteresis and the frequency of the current regulator, respectively, as a function of the current.
摘要:
The system provides for the commutation of a brushless direct-current motor. A virtual star is provided that is analogous to the motor. The virtual star is formed of resistors. A comparison device continuously comparing the voltages of the two star center points of the motor star and the virtual star in all phases. The comparison results are used to generate a signal for controlling the commutation.
摘要:
A method for regulating the temperature in a printing plate imaging unit of a printing press, particularly an offset printing press, the imaging unit being operable with laser light generated by a laser diode unit which is switched on and off in accordance with an image pattern to be produced on the printing plate, includes operating, alternatively with the laser diode unit, a heat source arranged near the laser diode unit so that the temperature of the laser diode unit is as constant as possible.
摘要:
A roller frame including at least two rollers mounted in a housing between which a nip can be formed. The ends of the rollers are supported in rotary fashion in bearings and at least one of the rollers is embodied as an advancing roller and has an adjusting system by which it is possible to move the bearings of the advancing roller, thus changing the nip. The adjusting system has a rack and a pinion whose teeth engage with those of the rack and can be driven to rotate by a motor. It is possible to change the distance between the pinion and the rack by changing the tooth engagement depth between them.
摘要:
A drawer configured to be extended from and retracted into a furniture body. The drawer includes a bottom part; a front panel; two lateral frames; and a back wall connected via a corner joint to an end region formed with one of the lateral frames. Each corner joint including a first connecting part and a second connecting part pivotably connected to the first connecting part. The second connecting part includes detent means for connecting the second connecting part to either the first connecting part or the back wall. The first connecting part is connected to an adapter associated with the end region formed by the back wall with one of the lateral frames.
摘要:
A method and device for electrically braking an electric drive in a machine for processing printing material, includes a power electronics connected between the electric drive and a DC voltage intermediate circuit. A further electric braking device is switchable between the electric drive and the power electronics. Upon a failure of a power system, a computer initiates a generator-type braking operation through the power electronics. The further electric braking device is switched on upon the failure of the power electronics.
摘要:
A method and a device for producing a film made of a thermoplastic material, wherein a plastic melt is blown up into a film bubble and is shaped into a desired film by a calibrating arrangement, and a downstream arranged flattening device. For providing as contactless as possible a guidance, calibration and flattening, film guidance elements are used with a laminar uniform air cushion between the film guidance element and the surface of the film bubble, without contact between the surface of the film bubble and the film guidance element.
摘要:
The invention relates to polymer-modified polyisocyanates and to polyurethanes prepared therefrom, and to their use in the production of polyurethane molded bodies. The polyisocyanates are modified with thermoplastic vinyl polymers having a number average molecular weight of from 15 to 90 kg/mol.
摘要:
An apparatus and a method for the selection of printing materials in a machine processing printing materials has at least one control computer. The operating data of the machine processing the printing materials is logged by the computer and a tolerance limit corresponding to the operating data registered is stored in the computer. When the tolerance limit is exceeded during a time interval, the printing materials produced in this time interval are registered in the control computer.
摘要:
Passenger conveyor (2) including an endless conveyor band (6) connected to a drive chain (8) at each lateral edge thereof and driven by a conveyor band drive (40) including an electric motor (48) and one drive output device (42) at each lateral edge of the conveyor band (6) for driving the respective drive chain (8), characterised in that the conveyor band drive (40) is arranged laterally outside of the conveyor band (6).