Abstract: A dental device is provided for fabricating dies from flexible impression material wherein the model, die and articulation mounting are accomplished in a single pouring. The device comprises a pair of recessed pivotal trays generally shaped to an individual's jaw. The member each includes inner and outer walls having internal ridges running vertically therealong at spaced distances and a base having predetermined spaced apertures thereabout to receive an insert. The trays are designed to be mounted face to face with a like member and open to 180.degree.. The tray includes hollow cylindrical portions in the rear thereof, engaged by a transverse element for pivoting thereabout. A vertical stop pin is mounted through the distal arm to maintain the respective spacing of the trays. The insert member has downwardly projecting portions extending through the base apertures, a base engaging the base of the tray and an upwardly extending rib which is located centrally within the walls of the tray.

Abstract: A pneumatic dilatator for introduction into the esophagus and for treatment of a constricted segment of the intestinal system of a living being contains an inflatable balloon and a tube of a given length which is passed through the balloon. The tube receives a gastroscope for observation during treatment. The balloon is preferably of cylindrical shape. Preferably it consists of a flexible material of little elasticity, such as polyurethane, which limits its diameter during an inflation to a given upper value.

Abstract: There is disclosed a two- to four-wire hybrid circuit of a telecommunication system. A line coupling circuit, preferably a transformer is connected to a terminal line. Between the coupling circuit and first and second amplifying means each assigned to a receiving branch and a transmitting branch of a transmission line, respectively there is arranged a balancing network composed of an attenuator, a first and a second hybrid impedance. The first impedance connected to the coupling circuit has a value matching the value of a coupled terminal line impedance which is effective at the four-wire side of the coupling circuit. The second impedance and the attenuator interconnect the outputs of the first amplifying means.

Abstract: A circuit arrangement for multi-address switching operations of digital encoded signals between a calling data terminal and a variety of called data terminals operating with different data transmission procedures is adapted for use with an electronic data switching system and comprises at least two interface circuits having input/output converting networks. External input terminals of these interface circuits are adapted for connection with respective input/output units of the electronic data switching system for each type of data terminal. Internal input/output terminals are connected to a storage unit for storing a multi-address message, including data information to be transmitted and identification information of the called data terminals.

Abstract: An electric gas blast circuit breaker is disclosed which has two stationary contact pieces. A switching unit is movable between closed and open positions for electrically bridging the contact pieces in the closed position and for electrically disconnecting the contact pieces in the open position whereby an arc develops when the switching unit is moved to the open position. A gas blast device blasts a stream of gas through the arc when the switching unit is moved to the open position. The switching unit includes a supporting body and a slide-contact ring made of an arc-resistant material. The ring slideably contacts one of the contact pieces in the closed position and is mounted on the supporting body so as to be electrically insulated therefrom. A plurality of elongated contact elements are disposed in the supporting body for electrically connecting the contact pieces when the switching unit is in the closed position.

Abstract: A method of making a Zener diode having a Zener voltage in the range of 2.4-3.3 volts. The PN junction is preferably formed by selective epitaxial deposition of P-type silicon on a previously oxidized N-type silicon wafer in an opened region where the oxide has been etched away. The N-type wafer may be a uniform silicon wafer with resistivity in the range of 0.004 to 0.006 .OMEGA.-cm or a low resistivity N-type wafer having a 5-20 .mu.m thick N-type silicon epitaxial layer with a resistivity in a range of 0.004-0.006 .OMEGA.-cm. The selectively deposited P-type layer may have a resistivity of 0.001-0.003 .OMEGA.-cm and a thickness of 1.5-3.0 .mu.m. The P-type layer is grown in a gas phase epitaxial reactor by etching the N-type wafer at a first temperature and then depositing heavily-doped silicon at a second, lower temperature.

Abstract: The energy interlock system is designed for a linear accelerator having no electron beam bending system. The accelerator emits electron pulses which are directed to a target for generation of X-ray pulses. The interlock system contains an ionization chamber, a discriminator and a switch. The ionization chamber is exposed to the X-ray pulses for measuring their intensity distribution. It comprises a control electrode and a plurality of electrode segments. The discriminator is connected for detecting energy inhomogeneities in the X-ray pulses. The switch is operated by the discriminator and connected to switch the accelerator on and off.

Abstract: In a central timer unit (CTU), incoming stochastically occurring control information, for example dial pulse data, which is to be buffered for execution after individually assigned delay times, is stored in a random access memory (RAM). Address linkage information is written into the RAM, with each piece of received control data, and chains the incoming data to other received data which is to be read from the RAM at the same absolute (real) time. Each piece of control data is automatically retrieved from the RAM, and retransmitted elsewhere in the telecommunications system, after its specified and predetermined buffering time in the CTU. The pieces of buffered data are individually linked to the CTU's internal time base, which is developed by a clock generator coupled to ring counter driven, hierarchially arranged, time control units.

Abstract: The filter arrangement for an X-ray apparatus contains an X-ray source for emitting a diverging beam of X-rays and a filter plate positioned in the beam of X-rays. The beam is symmetrical with respect to a center beam axis. The filter plate which serves for attenuation of the X-rays before they impinge on a target is mounted on a pivoting axis. The pivoting axis is preferably arranged remote from and transverse to the center beam axis. By pivoting the filter plate about the pivoting axis into a selected position, a selected radiation profile can be obtained on the target. The rotatable filter plate can thus replace a plurality of wedge filters.

Abstract: The relay contains an excitation coil, a U-shaped yoke with one of its legs serving as the core of the coil, and an armature to operate at least one switching contact of a contact carrier unit. This unit contains a supporting bridge which extends essentially perpendicularly to the axis of the coil and which carries the contact finger(s) of the switching contact(s). The contact carrier unit is fastened to the free leg of the yoke. One edge of the face end of the free yoke leg serves as knife-edge bearing for the armature. The armature is fastened to the free yoke leg by a holding element. In order to make the relay compact and easy to assemble, the armature is angularly formed, thus having a magnetically active leg and a free leg. The free leg which does interact with the core of the coil extends essentially parallel to the free yoke leg. The contact fingers are positioned essentially parallel to the axis of the coil. The supporting bridge is provided with a fastening piece.

Abstract: The system contains a fiber optical transmission line, a first light source for emitting a first light beam into a first end of the transmission line, and at least one first light sensitive element for receiving light from a second end of the transmission line. An energy storage device such as a capacitor is connected to the first light sensitive element for energizing various components. The system further contains a second light source for emitting a second light beam into the second end of the transmission line. This source is controlled in dependence upon information to be transmitted, preferably in dependence of a physical parameter. The system finally contains a second receiver element for receiving light from the first end of the transmission line. This element generates an electric output signal which is in accordance with the transmitted information.

Abstract: An improved zero crossing detector utilizes a voltage comparator having two inputs and an output. An amplifier supplies the electrical signal to one input and an inverting amplifier supplies the inverse of this signal to the other input of the voltage comparator. The voltage comparator changes its state when the relative polarities of its two inputs change.

Abstract: The collimator assembly comprises a collimator shielding block for blocking undesired X-rays and an insert piece inserted into the shielding block. The insert piece, which is made of a material of high atomic number, has an inner conical surface which defines the X-ray cone transmitting the insert piece and therefore the maximum field size which can be obtained for medical treatment. In order to supply different maximum field sizes, there are provided means for easily interchanging the insert in the collimator shielding block with another insert having a different interior conical dimension. By using inserts of different cone angles, which can easily be inserted into the shielding block, for instance by means of a screw thread from below the shielding block, morbid tissues of different sizes can be treated while the surrounding healthy tissue is fully protected.

Abstract: The energy interlock system contains a measuring device, a discriminator and a switch. The measuring device determines the level of the particle beam pulses which are emitted by the accelerator. For this purpose it contains a target which is exposed to the particle beam pulses. The discriminator determines whether the level of the particle pulses has crossed a predetermined value. The switch is operated by the discriminator. It is connected for supervision of the accelerator.

Abstract: A device for testing a digital electronic circuit, having a first BILBO for generating a pseudo-random test pattern, a second BILBO for analyzing a parallel-input signature, a decoder and at least one status indicator for indicating the status of a circuit under test.

Abstract: A modular telecommunication system comprises a plurality of switching blocks and a plurality of inter-connecting lines for interconnecting the switching blocks. Each of the switching blocks includes a multiplicity of line terminators each adapted to be connected to a respective data terminal. A communications controller is provided in each switching block for controlling local data exchange between pairs of line terminators connected thereto across real channels. A virtual channel controller is connected to the communications controller and controls remote data exchange across interconnecting lines via virtual channels between a locally associated data terminal and a data terminal associated with a different switching block. A central processing system is connected to the virtual channel controller and controls setting up switching operations within both the virtual channel controller and the communications controller.

Abstract: A modular telecommunication system comprises a plurality of switching blocks connected in parallel by interconnecting lines. Each of the switching blocks includes a multiplicity of line terminators each adapted to be connected to a data terminal. In each switching block there are provided (1) a central processing system for establishing communication links associated with a respective call, (2) a communications controller for controlling local data exchange between pairs of line terminators connected thereto across real channels, (3) a virtual channel controller for controlling remote data exchange across virtual channels to different switching blocks and (4) interface units arranged between the virtual channel controller and a respective one of the interconnecting lines.

Abstract: There is disclosed an input sensor unit for a fingerprint verification system. A sensor plate facing a fingerbed is composed of a transparent polymer which is elastic so as to form a latent topographic relief of a finger pattern. A sensing light beam is coupled into the sensor plate through one edge surface. An output light beam emitted through a planar surface of the sensor plate at the opposite side of the fingerbed is directed onto the light sensitive area of an electro-optical sensing array. In the optical path of the output light beam there is arranged an optical lens for focusing the output light beam onto the light sensitive area and an optical filter for masking out the direct light of the output light beam.

Abstract: Circuit arrangement for synchronizing a subordinate system, in particular a digital subscriber station, by a superordinate system, in particular a digital exchange, in a PCM time-multiplex telecommunication network. The circuit arrangement operates to evaluate only those synchronization bit combinations which lie at the beginning of a message signal block, thereby avoiding initiation of a re-synchronization during transmission of a block.