Patent Number: 
Section: claims

1. An irradiation device for proton or ion beam therapy comprising:a radiation source (3) that comprises a cyclotron or synchrotron arranged horizontally in a first plane (E3) for generating a treatment beam;a beam guiding device (5) installed downstream of the cyclotron or synchrotron, wherein the beam guiding device guides the treatment beam from the cyclotron or synchrotron into a therapy room (7);wherein the therapy room (7) is arranged in a second plane (E1) located above the first plane (E3), and wherein the therapy room comprises a treatment site (9) and an access (17);wherein a floor (B) of the therapy room comprises an entrance region (E) that enables the treatment beam to enter the therapy room (7) in the second plane (E1), and wherein the entrance region (E) is arranged between the treatment site (9) and the access (17) in the second plane;wherein the therapy room comprises a shielding that surrounds, at least in part, the entrance region (E), and wherein the shielding is open towards the treatment site (9) in the second plane so that the access (17) is arranged on the open side of the shielding (33) that is facing away from the treatment site (9);wherein the beam guiding device (5) is configured to guide the treatment beam (13) from the first plane of the cyclotron or synchrotron into the second plane of the therapy room (7) via the entrance region (E), and wherein the treatment beam (13) is deflected between the access and the treatment site within the therapy room in such a way that the treatment beam is directed towards the treatment site (9) and in an opposite direction of the access (17); andwherein the therapy room comprises at least one labyrinth (L) positioned in the second plane, and wherein the labyrinth is laterally offset in relation to the treatment beam (13) proceeding in the therapy room (7) and laterally offset to the shielding (33). 2. The irradiation device according to claim 1, wherein said treatment beam (13) entering said therapy room (7) in said entrance region (E) is conducted to a beam deflecting device (SU) and/or to a beam forming device (SF), which is/are arranged in said therapy room (7). 3. The irradiation device according to claim 1, wherein said treatment beam (13) proceeds towards said entrance region (E) below or above said access (17). 4. The irradiation device according to claim 1, wherein said shielding (33) comprises two wall regions (33a, 33b), between which said entrance region (E) is located, one of which said wall regions (33a, 33b) may be part of a shielding wall (35) of said therapy room (7). 5. The irradiation device according to claim 2, wherein said beam deflecting device (SU) and/or said beam forming device (SF) is/are arranged between wall regions (33a, 33b) of said shielding (33). 6. The irradiation device according to claim 5, wherein said shielding (33) has a base section (33c) connecting wall regions (33a, 33b). 7. The irradiation device according to claim 6, wherein said base section (33c) has a shielding reinforcement (41). 8. The irradiation device according to claim 7, wherein said wall regions (33a, 33b) of said shielding (33) dilate towards said treatment site as seen downstream from said entrance region (E). 9. The irradiation device according to claim 1, wherein said shielding (33) is symmetrically constructed. 10. The irradiation device according to claim 1, wherein the labyrinth (L) is provided between said access (17) and said treatment site (9) on both sides of said shielding (33). 11. The irradiation device according to claim 1, wherein at least one room (15) is arranged on said second plane for pre-treatment and after-treatment of patients treated at said treatment site (9) and for the stay of other persons. 12. The irradiation device according to claim 11, wherein said treatment beam (13) directed out of said entrance region (E) towards said treatment site (9) is directed away from said at least one room (15). 13. The irradiation device according to claim 1, wherein said treatment beam (13) is directed in an angle onto said treatment site (9). 14. The irradiation device according to claim 1, wherein said treatment beam (13) proceeds in parallel to the floor (B) of said therapy room (7). 15. The irradiation device according to claim 1, wherein said beam guiding device (5) is arranged in a third plane (E2). 16. The irradiation device according to claim 1, wherein said therapy room is one of multiple therapy rooms (7/1, 7/2, 7/3, 7/4) that are arranged in a curved manner to each other. 17. The irradiation device according to claim 1, wherein said therapy room is one of multiple therapy rooms (7) that are arranged in parallel to each other. 18. The irradiation device according to claim 17, wherein said multiple therapy rooms are arranged offset to each other. 19. The irradiation device according to claim 1, wherein said therapy room is one of multiple therapy rooms that are mirrored arranged and/or formed. 20. An irradiation device comprising:a radiation source,a beam guiding device, anda therapy room into which a treatment beam is directed, said therapy room comprising a treatment site and an access,characterized in thatsaid therapy room is arranged in a first plane;a shielding is provided in said therapy room, said shielding being open towards said treatment site and associated with an entrance region of said treatment beam into said therapy room;said beam guiding device is configured to direct said treatment beam from a second plane located above or below said first plane into said therapy room, within which said treatment beam is deflected and directed towards said treatment site so that said treatment beam is directed away from said access; andsaid access is arranged on that side of said shielding which is facing away from said treatment site, wherein a line that is coincident with said treatment beam as directed towards said treatment site passes through said access.