CN211019406U - Electron beam output guide coil fixing device for medical accelerator - Google Patents

Abstract

The utility model discloses an electron beam output guide coil fixing device for a medical accelerator, which comprises an iron box and an iron isolation plate; all process the via hole that has the beam current passageway on iron box and the indisputable division board, on two sets of coils of upper and lower and left and right sides in the output direction coil were fixed respectively on two mounting planes that are parallel to each other in the iron box, mounting plane perpendicular to beam current passageway place orientation, and keep apart through the shielding of indisputable division board in the middle of two sets of coils, the utility model provides an influence to another orientation outgoing position of electron beam when adjusting the outgoing position of an orientation of electron beam, for debugging work, especially brought very big convenience when implementing output electron beam automatic centering control.

Description

Electron beam output guide coil fixing device for medical accelerator

Technical Field

The utility model belongs to the technical field of medical electron linear accelerator, concretely relates to electron beam output guidance coil fixing device for medical accelerator.

Background

Medical electron linear accelerators are one of the most prominent types of radiation therapy equipment. As shown in fig. 1, the electron gun is installed at the rearmost end of the acceleration tube, and the electron beam emitted from the electron gun is injected into the acceleration tube after adjusting the position and shape of the magnetic field formed by the input guide coil and the beam prefocusing coil. The electrons are accelerated in the accelerating tube, and the exit position of the electrons is adjusted by a magnetic field formed by the output guide coil at the outlet of the accelerating tube and then enters the deflection system. The deflection system deflects the electron beam. Finally, the electron beam accurately falls on the X-ray target or the electron scattering film on the treatment head according to the required position, so that the rays meeting the relevant national standards are obtained on the treatment plane of the patient.

The output guide coil is used for adjusting the track and the direction of the electron beam output from the accelerating tube, so that errors caused by installation and processing can be corrected, and powerful guarantee is provided for industrial production. The coil is controlled by a precise program-controlled power supply, the size of the current of the coil can be directly adjusted by a computer, and the production and debugging of equipment are facilitated. The output guide coils are wound on the four iron cores and divided into an upper group, a lower group, a left group and a right group, two coils of each group are connected in series and are powered by a precise program control power supply, and the output position of the electron beam current is controlled by generating corresponding magnetic fields in the upper direction, the lower direction or the left direction and the right direction by changing the current flowing in the coils. The upper and lower coils adjust the output position of the electron beam in the up-down direction; the left and right coils adjust the output position of the electron beam in the left and right directions.

The four output guide coils are arranged in a box made of electric pure iron to form magnetic shielding, and as shown in figure 2, the mutual interference of an inner magnetic circuit and an outer magnetic circuit is prevented. When the electron beam accelerated to be close to the light speed by the accelerating tube passes through the beam flow channel, the current in the output guide coil is adjusted, the magnetic field formed in the beam flow channel is changed, the advancing directions of the electron beam in two mutually perpendicular directions are adjusted, and the electron beam is transmitted along the central axis of the accelerating tube.

However, in the practical use process, it is found that when the emitting position of the electron beam in one direction is adjusted, the position of the electron beam in the other direction is greatly influenced, which brings difficulty to the debugging work. Particularly, when the automatic centering control of the output electron beam current is implemented, the centering debugging in two directions mutually affects, and the satisfactory adjusting effect is difficult to achieve.

SUMMERY OF THE UTILITY MODEL

In view of this, the utility model provides an electron beam output guidance coil fixing device for medical accelerator can adjust the outgoing position of beam in one side, and does not have the influence to the outgoing position in another side.

Realize the technical scheme of the utility model as follows:

an electron beam output guide coil fixing device for a medical accelerator comprises an iron box and an iron isolation plate;

the through holes of the beam channels are processed on the iron box and the iron isolation plate, an upper group of coils, a lower group of coils, a left group of coils and a right group of coils in the output guide coils are respectively fixed on two parallel mounting planes in the iron box, the mounting planes are perpendicular to the direction of the beam channels, and the middle of the two groups of coils are shielded and isolated through the iron isolation plate.

Has the advantages that:

the utility model provides an influence to another direction outgoing position of electron beam when adjusting the outgoing position of an orientation of electron beam, for debugging work, especially brought very big convenience when implementing output electron beam automatic centering control.

Drawings

Fig. 1 is a schematic electron beam flow path diagram.

Fig. 2 is a schematic diagram of an output guidance coil box installation.

Fig. 3 is a schematic structural diagram of the present invention.

The device comprises an electron gun 1, an input guide 2, a prefocusing 3, an accelerating tube assembly 4, an output guide 5, a deflection system 6, an iron box 7, an iron isolation plate 8, an upper coil, a lower coil and a left coil and a right coil 10.

Detailed Description

The present invention will be described in detail below with reference to the accompanying drawings by way of examples.

The utility model provides an electron beam output guidance coil fixing device for medical accelerator, upper and lower among the prior art, about, two sets of coils install on a plane, then adorn in the box of electrician's pure iron preparation, though formed the magnetic screen like this, prevent that inside and outside magnetic circuit from interfering mutually, nevertheless inevitable brought the mutual interference of two sets of magnetic circuits. Therefore, the size of the iron box 7 along the beam passage direction is increased, the upper and lower coils 9 and the left and right coils 10 are respectively arranged on two mounting planes in the iron box 7, and the iron isolation plate 8 is additionally arranged in the middle for magnetic shielding, so that the mutual interference of an inner magnetic circuit and an outer magnetic circuit is avoided, and the mutual interference of the magnetic fields of the two groups of coils is also avoided, and the specific structure is shown in fig. 3.

And winding the enameled wire meeting the design requirement on a wire package framework for the required number of turns. After winding, the iron core is installed on the framework, four coils are respectively installed in a box made of electrician pure iron according to an upper group, a lower group and a left group, the middle partition plates of the two groups of coils are installed, the upper coil and the lower coil (the left coil and the right coil) are connected in series according to requirements, lead-out wires are connected to corresponding wiring rows, an output guide coil box is sleeved outside an output vacuum tube of the accelerating tube, and the output guide coil box is adjusted to enable the two groups of coils to be respectively located at the upper position, the lower position, the left position and the right position of the output vacuum tube of the accelerating. The two groups of coils are respectively connected with a precise program-controlled power supply capable of bidirectionally regulating output current, and the current in the output guide coil can be conveniently regulated by regulating the power supply through a computer, so that the size and the direction of a magnetic field formed by the output guide coil can be regulated. Thus, when the electron beam passes through the magnetic field, the emission position and direction are changed according to the magnetic field, and the two directions do not affect each other.

In summary, the above is only a preferred embodiment of the present invention, and is not intended to limit the scope of the present invention. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims (1)

1. An electron beam output guide coil fixing device for a medical accelerator is used for fixing an upper group of coils, a lower group of coils, a left group of coils and a right group of coils in the output guide coils, and is characterized by comprising an iron box and an iron isolation plate;

the through holes of the beam channels are processed on the iron box and the iron isolation plate, an upper group of coils, a lower group of coils, a left group of coils and a right group of coils in the output guide coils are respectively fixed on two parallel mounting planes in the iron box, the mounting planes are perpendicular to the direction of the beam channels, and the middle of the two groups of coils are shielded and isolated through the iron isolation plate.

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