Dental X-ray photographic device

Claim 3

A device as claimed in claim 1, in which the hollow-anode X-ray tube is mounted on the longitudinal axis of said housing or on an axis parallel thereto, and said other X-ray tube for intra-oral and extra-oral photography is offset laterally relative to the hollow-anode X-ray tube.

Claim 4

A device as claimed in claim 1, in which said other X-ray tube for intra-oral and extra-oral photography is arranged within said housing on the axis of said hollow-anode X-ray tube but positioned behind said latter tube.

Claim 5

A device as claimed in claim 1, in which the longitudinal axis of said other X-ray tube is at an angle to the longitudinal axis of the hollow-anode X-ray tube.

Claim 6

A device as claimed in claim 2, in which the cathode filament systems for the two X-ray tubes are mounted in a common casing.

Claim 7

A device as claimed in claim 5, in which said common casing is secured to mounting means which includes a target in alignment with the cathode filament for said second X-ray tube and a side window through which X-rays from said target are beamed.

Claim 8

A device as claimed in claim 6, which includes a protecting tube for the anode tube, said protecting tube being displaceable relative to the housing and in the axial direction of the anode tube in such manner that in a first, extended position it encloses the anode tube while in a second, withdrawn position the anode tube projects outwardly through an aperture provided in the protecting tube, and wherein windows for the outward transmission of X-rays from said target are provided in said housing and in said protecting tube at positions such that the windows are aligned with said side window when the protecting tube is in said position inclosing the anode tube, whereby the protecting tube only unmasks the radiation transmission aperture of that X-ray tube which is operational.

Claim 9

A device as claimed in claim 1, in which the cathode casing of said other X-ray tube is formed from a ceramic based material such as a ceramic oxide.

Claim 10

A device as claimed in claim 1 wherein the arrangement of prefiltering material on the head of the tube containing the anode is such that uniform prefiltering of the radiation occurs over the beam angle necessary for full-mouth photography.

Claim 11

A protecting tube for the anode tube of a device for use in the production of dental X-ray photographs comprising two separate X-ray systems, one of which comprises a hollow-anode X-ray tube mounted in a housing and including an anode tube projecting from the housing for extra-oral photographs and the other of which comprises an X-ray tube provided in the housing for intra-oral and extra-oral photographs, said other X-ray tube being mounted to direct its emitted X-rays at an angle of substantially 90* to the longitudinal axis of the hollow-anode X-ray tube, said protecting tube a. being displaceable relative to the housing and in the axial direction of the anode tube in such manner that in a first, extended position it encloses the anode tube while in a second, withdrawn position the anode tube projects outwardly through an aperture provided in the protecting tube and b. having a window for the outward transmission of X-rays from said other X-ray tube, said window being provided in the housing at a position such that it is aligned with the path followed by X-rays from said other X-ray tube when the protecting tube is in its first, extended position, whereby the protecting tube only unmasks the radiation transmission aperture of that X-ray tube which is operational.

Claim 12

A protecting tube for the anode tube of a device for use in the production of dental X-ray photographs comprising two separate X-ray systems, one of which comprises a hollow-anode X-ray tube mounted in a housing and including an anode tube projecting from the housing for extra-oral photographs and the other of which comprises an X-ray tube provided in the housing for intra-oral and extra-oral photographs, said other X-ray tube being mounted to direct its emitted X-rays at an angle of substantially 90* to the longitudinal axis of the hollow-anode X-ray tube, said protecting tube a. being displaceable relative to the housing and in the axial direction of the anode tube in such manner that in a first, extended position it encloses the anode tube while in a second, withdrawn position the anode tube projects outwardly through an aperture provided in the protecting tube and b. having a window for the outward transmission of X-rays from said other X-ray tube, said window being provided in the housing at a position such that it is aligned with the path followed by X-rays from said other X-ray tube when the protecting tube is in its first, extended position, whereby the protecting tube only unmasks the radiation transmission aperture of that X-ray tube which is operational.