SU197773A1

SU197773A1 - Spherical diaphragm for radiotherapy apparatus

Info

Publication number: SU197773A1
Application number: SU7400906552A
Authority: SU
Inventors: А.Э. Атовмьян; Н.С. Губарев; И.А. Давыдова; А.Б. Литван; В.К. Яголковский
Original assignee: Atovmyan A E; Gubarev N S; Davydova I A; Litvan A B; Yagolkovskij V K
Priority date: 1974-06-16
Filing date: 1974-06-16
Publication date: 1978-04-30

Description

Сферические диафрагмы дл аппаратов лучевой терапии, содержащие корпус, механизм открывани и закрывани , механизмы дл взаимного перемещени элементов блока, известны .Spherical diaphragms for radiation therapy devices, comprising a housing, an opening and closing mechanism, mechanisms for the relative movement of the elements of the unit, are known.

Предлагаема диафрагма отличаетс тем, что в ней установлено восемь клиновидно-сферических сегментов, образоваиных двум сферическими поверхност ми и двум плоскост ми , проход щими через общий центр этих поверхностей . Такое выполнение диафрагмы позвол ет получить многогранный пучок без применени дополнительных устройств и повыщает защиту за границами многоугольных полей .The proposed diaphragm is characterized in that it has eight wedge-spherical segments formed by two spherical surfaces and two planes passing through the common center of these surfaces. This embodiment of the diaphragm allows to obtain a multi-faceted beam without the use of additional devices and increases the protection beyond the boundaries of polygonal fields.

В диафрагме установлены также направл ющие накладки с пазами, изготовленные из защитного материала, например вольфрама, что исключает прорыв защиты в местах стыка сегментов, независимо от их взаимного расположени , нри сохранении скольз щей св зи между ними.Guides with grooves made of a protective material, such as tungsten, are also installed in the diaphragm, which prevents breakthrough of protection at the junction of the segments, regardless of their relative position, while maintaining a sliding connection between them.

На фиг. 1 изображена предлагаема диафрагма в двух проекци х; на фиг. 2 - место стыка двух сегментов; на фиг. 3 - механизм дл .взаимного смещени сегментов; на фиг. 4 - принципиальна кинематическа схема перемещени сегментов.FIG. 1 shows the proposed diaphragm in two projections; in fig. 2 - the place of the junction of two segments; in fig. 3 - a mechanism for reciprocal displacement of segments; in fig. 4 is a basic kinematic pattern of moving segments.

7, 8 и 9, попарно объединенных в четыре блока , механизм открывани и закрывани блоков и четыре независимых механизма взаимного смещени диафрагм в блоках. Па фиг. 47, 8 and 9, pairwise combined into four blocks, a mechanism for opening and closing blocks and four independent mechanisms for the mutual displacement of diaphragms in the blocks. Pa figs. four

сегменты и корпус 1 условно разнесены дл больщей сности схемы. По сферической поверхности корпуса скольз т диафрагмы, образующие окно дл прохождени нучка излучени от источника. Каждый сегмент снабженsegments and body 1 are conventionally spaced for greater clarity of the circuit. A diaphragm slides along the spherical surface of the housing and forms a window for the passage of radiation from the source. Each segment is equipped with

направл ющей 10 или 11. Между собой сегменты всегда наход тс в скольз щей св зи благодар накладкам, креп щимс к сегментам сверху н снизу винтами, например, к сегментам 4 и 5 креп тс верхние накладки 12 нguide 10 or 11. Between themselves, the segments are always in a sliding connection due to the lining attached to the segments above and below with screws, for example, the segments 4 and 5 fasten the upper lining 12 n

13 и нижние накладки 14 и 15.13 and lower pads 14 and 15.

Пакладки делают из материала с защитными свойствами (например из вольфрама) и поэтому они вл ютс дополнительной защитой от излучени в стыках между сегментами.Packages are made of a material with protective properties (e.g. tungsten) and therefore they provide additional protection against radiation at the joints between the segments.

Claims

When expanding the segments of the patch, they go outside the exit window of the diaphragm and do not affect the irradiation field. In the formation of rectangular fields, the blocks are pairwise shifted or moved apart with respect to the geometric axis of the diaphragm O-O in two mutually perpendicular planes. The blocks formed by segments 2, 3 and b, 7 simultaneously move in a common plane, limiting the size of the floor in the direction of off-hook 8, 9, moving in the perpendicular plane, limiting the second dimension of the field. The blocks are shifted and moved apart by the fingers 16-19 moving in the guide grooves 20-23 of the diaphragm body. The axis of the fingers is always perpendicular to the spherical surface of the body. The fingers 16, 18 and 17, 19 enter the slots of the guide blocks of segments 2, 6 and 4, 8, respectively. The fingers 16 and 18 move in the housing when turning the driver 24 relative to the axis O-O from the handle 25 through the gear 26. The fingers 17 and 19 move when the driver 27 rotates from the handle 28 through the transmission 29. When moving apart the blocks of segments 2-3 and 6-7, driven by fingers 16 and 18, the blocks of segments 4-5 and 8-9 that are with them in a slidable connection, slides along the housing guide surface in the same direction as the blocks of segments 2-3 and 6-7. Since the guiding grooves of the segments 4 and 8 are parallel to the direction of movement and the fingers 17, 19 are fixed, the distance of the blocks of the segments 4-5 and 8-9 from the geometrical axis O-O of the diaphragm does not change. The blocks of segments 4–5 and 8–9 move in the perpendicular plane also with a constant distance of the blocks – segments, 2-3 n 6-7 from the geometrical axis of the diaphragm; About The diaphragm window shape is changed by changing the offset of the 3, 5, 7, 9 segments that are not connected to the fingers 16-19. The mechanism for cutting the corners of the field by displacing, for example, a block of segments 4-5 contains a toothed sector 30, rigidly fixed on the guide segment 5, a flange 31 in the bearings of the bracket 32 attached in the guide segment 4, and an irreversible toothed pair 33, the linking axis of the tribrack with the axis of the telescopic cardan roller 34. When the handle 35, which is fixed in the bearings of the diaphragm case, is rotated in a certain direction, the tribka 31 interacts with the sector 30, whereby the segment 5 shifts to the O-O axis, the segment 4 in the perp an angular direction, with the result that the latter slides along the plane of the segment 3. At the same time, the finger 17, which enters the groove of the guide segment 4, remains stationary. The mechanisms for moving a block of segments 2-3, 6-7 and 8-9 are similar to those described. The formula of isoorestance 1. A spherical diaphragm for radiotherapy apparatus, comprising a housing, an opening and closing mechanism, mechanisms for reciprocating the block elements, characterized in that, in order to obtain a multifaceted beam shape without the use of additional devices and enhancement of protection beyond the boundaries of polygonal fields, it has eight wedge-spherical segments formed by two spherical surfaces and two planes passing through the common center of these spherical surfaces.

2. The diaphragm of claim 1, characterized in that, in order to eliminate the breakthrough of the protection at the junction of the segments, regardless of their relative position, while maintaining a sliding connection between them, guide pads with grooves are installed in it, which are made from protective material, for example tungsten.

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