Abstract: The present invention relates to a digital radiography device with protection against electrical risks, having: a radiation source (10); a sensor (12) connected to an electronic card (13) of a computer (14), first and second assemblies (20, 21) isolated from each other from the galvanic point of view, the first assembly (20) comprising electronic means connected to the sensor (12), the second assembly (21) comprising means for supplying a voltage for supplying the sensor (12) during the presence of radiation and a voltage for supplying the sensor part of the card (13), and means for providing management of the sensor, recovery of the data and processing thereof; the two assemblies (20, 21) exchanging information by optical means.

Abstract: A medical apparatus for (radiation) diagnosis or therapy can be provided with moving parts 6. Such an apparatus must be provided with a collision detection device 26, 28, 30. A known collision sensor measures the supply current for the drive motor and hence induces a high degree of inaccuracy in the collision detection. According to the invention the force applied to the moving part (image intensifier 6) is measured directly on the relevant part so as to be compared with an expected value, an alarm signal being generated when a threshold value for the difference is exceeded. The expected value is calculated while taking into account all movement and acceleration parameters of the apparatus. The expected values can be calculated in advance and stored in a look-up table or can be calculated, preferably while using a model of the apparatus, during operation of the apparatus.

Abstract: The subject invention pertains to a novel method and apparatus for improving the efficacy of a medical treatment or diagnostic procedure by coordinating such treatment or procedure with a patient's breathing cycle. In a specific embodiment, the subject invention pertains to a novel method of coordinating a chest x-ray with a patient's ventilatory cycle. In a specific example, this invention concerns a novel device for interfacing a ventilator and an x-ray machine to ensure that an x-ray chest image can be taken at peak insufflation of the patient. The subject invention also relates to other medical procedures including, but not limited to, cardiac output measurement, chest imaging, inhalation therapy, oxygen delivery, blood pressure measurement, and pulse oximeter optoplethysmograms. By coordinating certain medical treatments and diagnostic procedures with a patient's breathing cycle, the subject invention improves the quality of medical care received by the patient.

Abstract: In an x-ray fluoroscopic imaging system including a portable cabinet, at least one monitor, a support arm, an articulated arm assembly connecting the support arm to the cabinet, a C-arm carried by the support arm assembly, an x-ray source and detector located at opposing locations on the C-arm, and a control panel mounted on the source or the detector, three “x-ray on” lighted indicators are disposed at visible locations in the system, one of these indicators being a switch with a light-up perimeter on the control panel, the second being incorporated in the monitor, and the third being incorporated in the cabinet.

Abstract: An X-ray source interlock kit includes a probe-based portion integral with an X-ray source in communication with a peripheral-based portion, the interlock kit serving as an interface between an X-ray treatment system and a given class of peripheral devices. Peripheral devices are classified based on their shielding characteristics and whether or not radiation is permitted with the device, and include, for example, a stereotactic frame, a probe adjuster, and a photodiode array. The probe-based portion includes a probe side bushing having two optical source-detector pairs housed therein and interlock electronics, which accomplish signal processing as required. The peripheral-based portion is the form of a peripheral side bushing which is coded with the shielding and radiation information for a given class of peripheral devices.

Abstract: An improved x-ray analyzer may be portable to permit on-site or outdoor analysis without the possibility of emitting harmful x-rays. A housing of the analyzer contains an x-ray generation system for generating x-rays and irradiating the x-rays onto a sample under analysis, an x-ray detection system for detecting x-rays emitted by the sample in response to irradiation of the sample by x-rays by the x-ray generation system, and a safety mechanism for permitting x-rays to be emitted from the housing only when a sample is under analysis. A normally-closed shutter is disposed between the x-ray generation system and a measurement window mounted to the housing through which x-rays are emitted. The safety mechanism includes a first switch which permits the shutter to be opened only when the housing is in contact with a sample under analysis so as to prevent the emission of x-rays from the housing when the housing is not in contact with a sample under analysis.

Abstract: A method and device for detecting and analyzing X-ray radiation with a detector unit which is placed in connection with the X-ray radiation. The detection unit is connected to a processing unit for processing the information which is received from the detection unit. The detection unit is placed directly in the radiation field of the X-ray radiation, and the detection unit is in the form of a matrix or a vector provided with one of more detector elements. The processing unit processes the information which is obtained from each detector element in the detection unit. In addition, a collimator is arranged in front of the detection unit, with the collimator being formed such that the radiation is reproduced substantially in dot form on the detector element.

Abstract: A rotary anode type X-ray tube is controlled by an X-ray emission control device. In the X-ray emission control device, the maximum permissible storage heat quantity which can be applied to the rotary anode of the X-ray tube is set, the anode storage heat quantity which is lowered based on the cooling characteristic of the rotary anode is calculated, the present anode storage heat quantity is calculated, and the imaginary anode storage heat quantity for the next X-ray emitting condition which is derived by calculation using the correction functions based on the anode input power, emission continuation time, anode rotation speed and focal point size, the anode input power of the next predicted X-ray emission, and X-ray emission continuation time is calculated.

Abstract: A method for modulating the intensity of an x-ray beam in an x-ray inspection system so as to maintain the highest penetration power and optimum image quality subject to keeping the ambient radiation generated by the x-rays below a specified standard.

Abstract: A portable and preferably hand-held X-ray generator for use in intraoral and other X-ray applications, and a new process of dental image acquisition which utilizes a novel receptor holder physically linked to the lightweight, portable generator, and a unique, articulating arm and cradle which allows one generator to be used in multiple operatories. The system's generator has a reduced X-ray output and much smaller focal spot area than conventional dental X-ray generators. This reduced X-ray output reduces the overall patient X-ray burden. The smaller focal spot also allows for improved resolution in the final image.

Abstract: An apparatus for medical diagnosis and/or therapy which includes an electromagnetic proximity sensor (20-1, 20-2, 20-3, 20-4) which detects the presence of an object (for example, 28) directly in front of the sensor. By coupling the main drive directions 34-1, 34-2, 34-3 and 34-4 to the proximity sensors in such a manner that each main drive direction (for example, 34-4) substantially halves the exterior angle (.alpha..sub.4) between the two neighbouring proximity sensors (20-1, 20-4) and by inhibiting the displacement in the associated main drive direction (34-4) by these two neighbouring proximity sensors, it is achieved that all clearing movements remain possible and all movements leading to collisions are inhibited.

Abstract: In an X-ray tube with a hydrodynamic slide bearing, an electron beam is caused to strike the focal point track area F on its rotary anode, which then emits X rays. An X-ray emission control device that sets the conditions for emitting the X rays stores as data the rises and drops in the temperature at the electron beam incident point and the other part on the focal point track surface of the anode. On the basis of the data, the input permission or inhibition conditions for the X-ray tube at every moment are calculated and the resulting conditions are displayed on a display unit. As a result, it is possible to perform a computing process in advance to determine whether or not X rays can be emitted under specific conditions without a permitting the rotary anode in the X-ray tube with a hydrodynamic slide bearing to melt and then display the results, thereby enabling a safe, efficient photographing control.

Abstract: The present invention, in one embodiment, is an interference detection assembly for detecting patient and patient table interference with a gantry of a computed tomography system. The assembly, in one form, includes a frusto-conical capacitive plate secured to a leading frusto-conical surface of the gantry bore. The capacitive plate is coupled to a control unit which detects changes in the capacitance of the capacitive plate. When the plate is discharged below a threshold charge, the control unit generates a signal which may be used to automatically interrupt a scan.

Abstract: An imager control system with contact detection capability for positioning a movable imaging element structure with respect to a subject includes a collar assembly disposed around at least a portion of the imaging element structure disposed towards a subject region; a plurality of sensor elements disposed in a sensing pattern in the collar assembly, each sensor element having a number elastomeric electrodes coupled together in series; and a processing unit coupled to the sensor elements so as to detect contact between the collar assembly and a subject of examination as a function of a change in resistance in one or more elastomeric electrode resulting from deformation of the electrode upon contact with the subject. The elastomeric electrodes are made of a flexible material in which conductive particles have been embedded such that electrode exhibits a change in electrical resistance in response to physical deformation.

Abstract: Radiation delivered to an object (13) is gathered by a detector unit (91). A central processing unit (18) reverse calculates the radiation delivered by using attenuation factors of the object (13) and exit radiation signals (92) generated by the detector unit (91). The delivered radiation is displayed on the screen of a monitor (70). Simultaneously, a radiation map from a planning system can be displayed. Thus, the amount of radiation delivered to object (13) is measured and can then be verified and displayed. A portal imaging system (90) can contain detector unit (91).

Abstract: A safety system including two command buttons (7, 8) spaced apart from one another geographically, and obliging an operator to use both his hands to control a radiology appliance, or one hand and a foot, is completed by a protocol including, on a single button (7), a short pulse followed by a long pulse during which the maneuver is carried out.

Abstract: An ultrasonic ranging system for providing a distance to a subject signal for use in positioning a movable imaging element support structure with respect to a subject of examination includes a collar assembly disposed around a portion of the imaging element structure disposed towards an imaging region; a plurality of ultrasonic transducers disposed in a sensing pattern around the collar assembly; and an ultrasonic ranging processing unit coupled to the transducers to control processing of ultrasonic ranging signals from the transducers. The transducers are typically disposed in one or more rows on the surface around the circumference of the collar assembly such that the lobes of ultrasonic signals generated provide a desired ranging field.

Abstract: A capacitive proximity detection system for positioning a movable radiation imaging element support structure with respect to a subject includes a plurality of sensor plates disposed in a collar assembly around a portion of an imaging component disposed towards a subject; a multiplexer coupled to the plurality of capacitive plate elements and adapted to selectively electrically couple the sensor plate elements in one of a plurality of sensing range modalities; and a capacitive sensing processor coupled to the sensor plate elements via the multiplexer so as to detect proximity of object to the sensor plate as a function of the capacitance between the sensor plates and the subject. The imaging system typically further includes a shield system coupled to the multiplexer and disposed so as to focus the capacitive sensing of the sensor plate elements towards the subject.

Abstract: A portable and preferably hand-held X-ray generator for use in intraoral and other X-ray applications, and a new process of dental image acquisition which utilizes a novel receptor holder physically linked to the lightweight, portable generator, and a unique, articulating arm and cradle which allows one generator to be used in multiple operatories. The system's generator has a reduced X-ray output and much smaller focal spot area than conventional dental X-ray generators, which reduces the X-ray output and the overall patient X-ray burden. The smaller focal spot also allows for improved resolution in the final image.

Abstract: A computerized tomography apparatus is disclosed which reconstructs a tomography image of data from multi-directional projection data in a period of time less than the time required for a scan operation for data acquisition and displays the tomography image after a lapse of a given period of time from the termination of the scan operation. This avoids the time interval between scan and image display becoming irregular. Accordingly, tomography images can be displayed successively like motion picture to observe the internal movements of a section of a human body under examination in real time.

Abstract: A high-voltage power supply and regulator circuit for an X-ray tube which utilizes solid state switching devices and provides protection against failure of the switching devices due to transient voltage spikes. The high-voltage protection circuit includes an inductor intercoupled with a high-voltage clamp, such as a series of solid state current conducting devices in parallel with the inductor. The protection circuit further includes a diode connected in parallel with the capacitor for preventing the voltage across the regulator circuit from reversing polarity. A shielded voltage divider may further be provided to accurately measure the voltage output and produce feedback control signals. Still further, a discharge module may be provided on high-voltage cables connecting the regulator circuit to the X-ray tube in order to discharge any capacitive voltage remaining on the cables between pulses, in order to eliminate any tail on the output waveform.

Abstract: Computer control of a multi-axis radiographic instrument is utilized to prevent contact between moving surfaces of the instrument based on soft limits. The soft limits are established from a legal state table incorporating all combinations of axis movement of the equipment and relating those combinations to contacting or non-contacting states. The legal state table may be used to map efficient paths between a start and ending position and may be augmented with non-contacting transducers which may sense patient movement not incorporated into the legal state table.

Abstract: An X-ray computed tomography apparatus includes a rotating frame section, an X-ray generating system mounted on the rotating frame section, electric power transmission means constituted by a slip ring and a brush and designed to supply electric power to the X-ray generating system, and a detection means for detecting an electric power supply state in the electric power transmission means.

Abstract: A method and apparatus employed in an X-ray apparatus for compensating for attenuation caused by a subject to perform an improved X-ray exposure. A table is created comprising entries accessible via power and attenuation values. Each of the entries includes a first value T representing a time for radiation in the system to reach a base ion count, and a second value C representing an offset ion count from the base ion count. A first set of entries in the table are referenced using a first power setting, and a first base ion count is determined based upon the first power setting, and a maximum radiation exposure is determined for the first power setting and a subject's mass. Then, an X-ray emitter is activated until a current ion count from a radiation sampling means has exceeded the base ion count or total radiation emitted has exceeded the maximum radiation allowed for the given mass of a subject.

Abstract: In mammographic examinations, the breast being examined is compressed with increasing force between a pressure plate and a support platform. A method and apparatus are disclosed for generating an optimal compression pressure which is adapted to the size of the breast being examined, so as to insure reliably high image quality. In the method and apparatus, the compression pressure of the pressure plate against the breast is controlled so that the increase in compression force is stopped when a change in breast thickness reaches a predetermined value. The appartus includes a measuring device for establishing the distance between the pressure plate and the support platform, thereby establishing the thickness of the breast as the compression force increases, and a control device which stops the increase in the force of compression when the change in this distance reaches a predetermined value.

Abstract: A method and apparatus employed in an X-ray apparatus for compensating for attenuation caused by a subject to perform an improved X-ray exposure. A table is created comprising entries accessible via power and attenuation values. Each of the entries includes a first value T representing a time for radiation in the system to reach a base ion count, and a second value C representing an offset ion count from the base ion count. A first set of entries in the table are referenced using a first power setting, and a first base ion count is determined based upon the first power setting, and a maximum radiation exposure is determined for the first power setting and a subject's mass. Then, an X-ray emitter is activated until a current ion count from a radiation sampling means has exceeded the base ion count or total radiation emitted has exceeded the maximum radiation allowed for the given mass of a subject.

Abstract: A high-voltage power supply and regulator circuit for an X-ray tube which utilizes solid-state switching devices with feedback control for real time monitoring and protection against failure due to excess current or voltage spikes. The apparatus includes a DC supply circuit utilizing a first feedback control loop and silicon controlled rectifiers to regulate the output of a high-voltage transformer. The apparatus further includes a regulator circuit utilizing a second feedback control loop and a series of FETs to product a continuous or pulsed output of precise magnitude and phase. Shielded voltage dividers are provided to accurately measure the voltage outputs and produce feedback control signals. Discharge modules on the high-voltage cables connecting the power supply to the X-ray tube discharge any capacitive voltage remaining on the cables between pulses, so as to eliminate any tail on the output waveform.

Abstract: An X-ray radiographing apparatus is provided with an interlock mechanism to avoid mutual interference of movable elements such as an X-ray unit, a compression cone, a table, a tabletop and a spot-film device. When a judging element judges, in response to information outputted from a position detecting element of the movable elements and switches operated by an operator, that interlock should be done, an interlocking element is worked, and then a teaching unit is worked. Thus, the interlocked state itself and how to unlock from the interlocked state can be taught to the operator with graphic images by the teaching unit.

Abstract: A protection cover includes a pressure responsive means mounted within the cover along its inner wall surface and which operates responsive to external forces to be exerted upon contact with a neighboring object. The protection cover is provided at a portion where physical contact may occur between any of movable or rotating component devices of an X-ray diagnostic apparatus, such as, an X-ray exposure unit or an image intensifier, and a neighboring object which is in the path of the component devices, such as, a subject or a catheter table. The protection cover may, for example, be provided at a moving end of a component X-ray diagnostic apparatus, such as, the forward end of the image intensifier, or may be mounted, instead of being mounted on a movable component device, on a neighboring object at its side facing to the movable part of the component devices, such as, a stand section of the catheter table, which lies in the path of a moving part of the X-ray radiographing component devices.

Abstract: An X-ray apparatus has a motor for moving its components in different directions. A collision sensor is formed by a bladder attached to a component of the apparatus and deformation of the bladder produces a change in the pressure of air within the bladder. The bladder has an air vent to the atmosphere which can be sealed by operation of a valve. A pressure sensor produces two control signals when the pressure within the bladder exceeds first and second threshold levels respectively. The second threshold level is greater in magnitude than said first threshold level. The first control signal closes the valve and causes a motor control circuit to discontinue any application of electricity to the motor. The second control signal opens a switch through which electricity normally flows to the motor. A mechanism also is provided to simulate a collision by compressing the bladder to test the operation of the detection system.

Abstract: A high-voltage generator supplies an X-ray source with a high-voltage via at least one high-voltage cable. To protect the X-ray tube of the source against destruction by discharge phenomena in the X-ray tube, a damping impedance which is operative only from a high-frequency point of view is provided at the output of the high-voltage generator.

Abstract: A collision sensor specially adapted for a power driven x-ray imaging apparatus includes a face collision sensor and an edge collision sensor. The face collision sensor has two annular plates which are biased apart longitudinally by three flat springs which are equiangularly spaced apart around the perimeter of the plates. Three equiangularly spaced cables hold the plates in parallel planes with the springs prestressed and collapse to allow the plates to be compressed together. Two sets of three switches each reside at equal angular intervals between the plates, with at least one of the switches of the first set being actuated when any point across the face of the sensor has been moved a predetermined longitudinal distance. At least one of the switches of the second set is actuated when the point on the face of the sensor has been moved a further predetermined longitudinal distance. An edge collision sensor includes a closed air bladder which surrounds the face collision sensor and in which a vacuum is drawn.

Abstract: A discharge module positionable between a high-voltage power supply and an X-ray tube for discharging any capacitive voltage remaining on the cable connecting the same. The discharge module includes a low-voltage control portion which is optically coupled to a high-voltage portion that includes a switch for activating a discharging resistor series. The module also monitors the current through the X-ray tube to initiate a fault if the current exceeds a predetermined maximum.

Abstract: The generation of excessive electron radiation is prevented in an apparatus which comprises an accelerator means for generating and accelerating electrons. The accelerator comprises an electron injector for emitting injector pulses, an electron gun for receiving the injector pulses, a waveguide receiving electrons from the electron gun and a high frequency source for supplying RF signals for the generation of an electric field for accelerating the electrons in the waveguide and generating the electron beam which has a predetermined intensity level according to the amplitudes of the injector pulses. A sensing means senses the amplitudes of the injector pulses and generates sensing signals. The amplitudes of the sensing signals are compared with predetermined reference voltage values and the generation of the electron beam is prevented if the amplitudes of the sensing signals exceed the predetermined reference voltage value.

Abstract: A gantry (A) of a CT scanner system has an x-ray tube (10) and radiation detectors (14) which produce patient diagnostic data. An operator using a keyboard (20) or other manual controls operates the x-ray tube and other components of the gantry. The operator also causes a central processing unit (C) to process the diagnostic data with a selected algorithm to provide diagnostic information for display on a display (24). The same keyboard and displays are also utilized in routine service and repair processes. A system monitor (E) compares operating conditions sensed by sensors (50), such as operating temperatures and compares them with acceptable operating conditions. When the sensed conditions are unacceptable, a timer (60) is started and shuts down (68) gantry operation after a preselected duration. The operator can override (72) the timed shut down, but each such override is recorded (74) in permanent storage (32).

Abstract: A head-activated fluoroscopic control which is characterized in a preferred embodiment by a continuous wave infrared transmitter located in a cartridge adapted for attachment to eyeglasses, a headband or other headpiece worn by a surgeon or attending physician and a detector or receiver tuned to the frequency of the continuous wave infrared transmitter for receiving a partially collimated infrared signal beam and activating a fluoroscope. The infrared transmitter emits the collimated beam and the beam is received by the receiver when the surgeon's head is turned toward the fluoroscope monitor upon which the receiver rests or in which the receiver is mounted, to facilitate selective operation of the fluoroscope during surgery.

Abstract: A collision preventive device for medical equipment (such as readiotherapy equipment) having moving parts to which accessaries are disengageably attached includes a contact detection circuit in which the normally closed contact detector switches disposed on the moving part and on the accessary are all coupled in series, so that an occurrence of contact of the moving part or of the accessary attached thereto can be detected by a relay coupled across a current source in series with the contact detector switches.

Abstract: A high-voltage generating device for use with an X-ray tube comprises a converter circuit for rectifying, chopper controlling, boosting and rectifying an A.C. voltage from an A.C. power supply to apply a D.C. voltage to the X-ray tube, a tube-voltage detecting circuit for detecting a tube voltage of the X-ray tube to produce a signal corresponding to the detected tube voltage, a preset signal generator for generating a signal corresponding to a constant voltage, and a feed-back control circuit for controlling the chopper transistor of the converter circuit on the basis of the output of the preset signal generator at the start of operation and on the basis of the output of the tube voltage detecting circuit after the output of the tube voltage detecting circuit has reached a reference value.

Abstract: An X-ray tube exposure monitor for recording the emissions from a diagnostic X-ray tube. A photo diode is mounted inside the X-ray tube bulkhead and detects radiation from the X-ray tube. The photo diode is connected to a high gain amplifier and, in response to radiation being detected, the output of the amplifier sends an electronic signal to a microprocessor. The microprocessor records the emission duration and the temperature of oil around the X-ray tube and increments an exposure count. The recording and exposure count is stored in non-volatile memory which is read later by a service technician.

Abstract: An anode driving apparatus of a rotating anode X-ray tube includes a power source transformer connected to an AC power source, first and second taps, located at the secondary winding of the power source transformer, for outputting first and second AC voltages having the same phase, first and second switching elements respectively connected to the first and second taps and each made up of a solid state relay (SSR), an AC motor having a common terminal commonly connected to the first and second switching elements, a main terminal connected to a 0-voltage terminal of the power source transformer, and a subterminal connected to the 0-voltage terminal of the power source transformer via a phase shift capacitor, and a switching controller for turning on/off the first and second switching controller sequentially and continuously turns on the first and second switching elements, and sequentially applies the first and second AC voltages to the common terminal of the AC motor.

Abstract: An X-ray photographing apparatus includes first and second systems for photographing an object from different directions. A first arm of the first system supports a first X-ray tube thereon and is arranged to be rotatable. A second arm of the second system supports a second X-ray tube thereon and is arranged to be rotatable. When at least one of the arms is rotated, interference between the arms is prevented by an interference preventing device. The device has a storing section storing data relating to relative positions between the arms when at least one of the arms is rotated while an iso-center, i.e., the crossing point of X-ray beams emitted from the X-ray tubes coincides with the rotational centers of the arms.

Abstract: A dental x-ray diagnostics installation having a holder for film cassette and a holder for diaphragms of different sizes, which holder for diaphragms is positioned in an x-ray source so that the beam passes through the diaphragm aperture before reaching the subject. The diaphragms are interchangeable with one another and have different diaphragm apertures for the purpose of matching the x-ray beam cross-section to different film cassette formats.

Abstract: An x-radiator has a housing filled with electrically insulating fluid and having a radiation exit window, an x-ray tube disposed in the housing surrounded by the fluid and directing x-radiation through the exit window. During operation, the x-ray tube generates heat, causing an increase in pressure of the fluid in the housing. A protection circuit is provided which discontinues operation of the x-ray tube when the pressure of the fluid in the housing reaches a limit value. In order to prevent the protection circuit from unexpectedly discontinuing operation of the x-ray tube during a patient examination, the x-radiator also includes a warning circuit which generates a signal when the pressure of the fluid in the housing reaches a threshold level, the threshold level being below the limit value.

Abstract: A system and method for monitoring progress of a radiographic exposure is disclosed. The system samples the cumulative radiation as an exposure progresses, and aborts the exposure if the rate of rise in cumulative radiation is insufficiently low to cause a good exposure. Similarly, the system will terminate an exposure early, at a properly timed out interval, even if the radiation accumulation rises excessively fast due to an erroneous system set up.

Abstract: A MAS regulating system for high frequency medical X-ray generator produces a control signal to stop the exposure when the milliamp-seconds delivered by the X-ray tube becomes equal to or greater than a desired maximum amount set by an operator. The system comprises a converter circuit for converting a signal corresponding to a desired MAS value set in by the operator into a first digital signal having a predetermined format. A digital integrator circuit integrates and converts the actual MA current in the X-ray tube to a digital MAS signal corresponding to the actual MAS value of the current in the X-ray tube and in the same predetermined format as the first digital signal. A comparing circuit compares the first and second digital signals and produces a control signal to stop the exposure when the second digital signal is greater than the first digital signal.

Abstract: An X-ray tube having two individually energizable cathode filaments. If a primary filament is shorted to a cathode cup, a switch mounted inside the tube housing is thrown to couple a second filament to a filament energization signal. This avoids the necessity in replacing the X-ray tube if the primary filament is shorted and lengthens the effective life of the X-ray tube.

Abstract: The present invention is directed to an X-ray diagnostics installation having control elements for control of specific components of the installation. In order to prevent inadvertent actuation of the elements, an activation switch must be actuated to cause each of the control elements to be effective for a predetermined time. The length of the predetermined time can be increased by actuation of one of the control elements following the actuation of the activation switch.

Abstract: A switch mechanism for an image intensifier hood in an x-ray diagnostics system is connected to a motor for moving the x-ray image intensifier toward and away from an examination subject. If the hood inadvertently comes into contact with the examination subject or a technician, the hood is displaced thereby actuating the switch mechanism and disengaging the motor to stop movement of the x-ray image intensifier, thereby avoiding injury to the examination subject and technician and avoiding damage to the x-ray image intensifier. The switch mechanism is constructed such that actuation thereof occurs upon the presence of forces acting on the hood in the direction of the luminescent screen surface or a direction perpendicular thereto, and each intermediate direction.

Abstract: A circuit for operating an X-ray tube, such as in a medical diagnostics apparatus, is connected with a high-voltage generator and a switch mechanism for connecting and disconnecting the X-ray tube to the high-voltage generator. A resistor is disposed in a circuit branch which can be connected in parallel across the X-ray tube by a switch controlled by the aforementioned switch mechanism. If the X-ray tube is disconnected from the power source, the switch closes the circuit branch and causes the resistor to be connected across the X-ray tube. As a result, the X-ray tube voltage decreases relatively quickly after the high-voltage is disconnected. The resistor across the X-ray tube may be a variable resistor, such as a high-voltage triode.

Abstract: In an exemplary embodiment a compression carriage, adjustable by means of an electromotor, supports a compression localizer with which a switch is associated which disconnects the motor when the compression localizer engages the radiography subject. The connection between the motor and compression localizer can be selectively disengaged manually so as to allow manual movement of the compression localizer while the motor remains deenergized.