DE1095956B - Diagnostic X-ray apparatus with automatic exposure in one-button operation and with mAs relay in two-button operation - Google Patents

Description

GERMAN

The invention relates to a known diagnostic X-ray apparatus with a control element for the mAs product, with another control element for the X-ray tube voltage and with a mAs relay for the termination of the duration of the recording.

According to the invention, the device can be switched from operation with mAs relays. to operate with automatic exposure, in the latter case, known means are automatically switched on for setting the X-ray tube current depending on the setting of the control element for the tube voltage, so that only A regulation of the X-ray tube voltage is still required.

The invention is explained in more detail below with reference to the exemplary embodiment illustrated in the figure. In the figure, the greatly simplified circuit arrangement of an X-ray diagnostic apparatus is shown with the X-ray tube 1, the subdivided high-voltage transformer 2a, 2b and the heating transformer 3. The X-ray tube voltage is set by pressing the setting button 4, which causes the current collector 5 on the Winding of the regulating transformer 6 is adjusted. The set high voltage value is indicated by a pointer 7 coupled to the rotary knob 4 on a kV scale 8. Depending on the X-ray tube voltage setting, an only schematically indicated control device 9 for the X-ray tube current is influenced in such a way that it lowers the X-ray tube current during the subsequent exposure from a certain initial value in such a way that the tube load limit is not exceeded.

The X-ray apparatus shown can either be operated with an automatic exposure device or with a mAs relay. In both cases, the recording is switched on via a schematically indicated control device 10 by closing the contact 11 of a switch-on contactor 12 arranged in the primary circuit of the high-voltage transformer 2 a, 2 b. When the apparatus is set to one-button operation as shown in the figure, the rotary knob 13 for setting the mAs product is turned all the way to the left in two-button operation, whereby the pointer 14 coupled to the rotary knob 13 for a mAs scale 15 is at one end this scale moves 15. As a result of this process, a switch 16 is brought into the position shown in the figure and an illumination lamp 17 for the scale 15 is extinguished. In practice, these switching operations are achieved by means of a relay, the excitation circuit of which is closed by means of the setting knob 13 in its left end position by means of a spring contact. The automatic exposure device 18, the ionization chamber 19 of which is arranged between the object 20 and the film cassette 21, closes when the diagnostic X-ray apparatus is reached
with automatic exposure device in one-button operation and with mAs relay
in two-button operation

Applicant:

Siemens - Reiniger -Werke

Aktiengesellschaft,
Erlangen, Luitpoldstr. 45-47

Herbert Schmitmann, Erlangen,
has been named as the inventor

for the optimal film blackening required dose a contact 22 in the circuit of a cut-off contactor 23, whose normally closed contact 24 in the primary circuit of the high-voltage transformer 2 a, 2 6 is then opened.

The device switches over to two-button operation automatically when the doctor sets a mAs value on scale 15. As soon as the pointer 14, which is coupled to the setting button 13 for a mAs relay, is moved to the right from its zero position, the contact 16 in the circuit of the switch-off contactor 23 switches over, whereby the contact 22 controllable by the automatic exposure unit 18 is rendered ineffective. The X-ray tube voltage is now switched off by a mAs relay. For this purpose, a measuring capacitor 26 and a variable resistor 27 are connected between the two secondary winding halves of the high-voltage transformer 2 a, 2 b in shunt to a fixed resistor 25. The desired mAs product can be set at the resistor 27 by means of the rotary knob 13. As soon as the X-ray tube voltage is switched on by closing the contact 11, part of the X-ray tube current that then sets in charges the capacitor 26 increasingly positively until the ignition voltage of a gas discharge interrupter 28 is reached, which then, by means of a relay 29 arranged in the anode circuit of the tube 28, the contact 30 in Circuit of the shutdown contactor 23 is closed.

The coupling of the setting element for the mAs product with the converter as described above

009 680/41?

switch, a special setting button for switching the operating mode is saved and thus the Clarity of the control panel increased. By automatically switching the lighting on and off for the mAs scale when switching over, the operator is aware of the change in the operating mode made clear.

Claims (3)

PATENT CLAIMS: IO 1. Diagnostic X-ray apparatus / with a control element for the mAs product, with another control element for the X-ray tube voltage and with a mAs relay for ending the duration of the exposure, characterized in that an automatic exposure device is provided in addition to the mAs relay by means of a switch from operation with mAs relay to operation with automatic exposure unit can be switched, in the latter case known means are automatically switched on for setting the X-ray tube current according to the setting of the control element for the X-ray tube voltage. 2. Diagnostic X-ray apparatus according to claim 1, characterized in that the switch with is coupled to the control element for the mAs product. 3. Diagnostic X-ray apparatus according to claim 1, characterized in that the lighting is a mAs scale can be switched off via the switch when switching to operation with automatic exposure. 1 sheet of drawings © 009 680/415 12.60