CN109860011B - X-ray tube integrated with ion pump - Google Patents

Abstract

An X-ray tube with integrated ion pump, comprising a power supply unit, an ion pump module and an X-ray module; the power supply unit includes a low-voltage power supply, and the low-voltage power supply is connected to a primary coil of a transformer; the X-ray module includes an X-ray generator an anode and an X-ray generating cathode, the X-ray generating anode and the X-ray generating cathode are connected to both ends of the first secondary coil of the transformer through a first coupling circuit; the ion pump module includes a vertically arranged ion pump anode and an ion pump cathode, the ion pump anode and the ion pump cathode are connected to both ends of the second secondary coil of the transformer through a second coupling circuit. The invention integrates the high voltage power supply of the vacuum ion pump and the high voltage power supply of the X-ray source, so that the X-ray tube with the integrated ion pump provided by the invention has the advantages of small size, light weight, simple structure and long service life.

Description

X-ray tube with integrated ion pump

technical field

The invention relates to the technical fields of microfocus X-ray imaging, X-ray nondestructive testing, X-ray diffraction, X-ray fluorescence spectroscopy, ion pump and the like, in particular to an X-ray tube with integrated ion pump.

Background technique

X-rays are produced by bombarding high-atomic-weight metal targets with high-speed electrons. A typical X-ray tube includes a metal anode target, a cathode electron source, and a high voltage power supply. Conventional X-ray tubes use a thermally emitting tungsten filament cathode to generate the electron beam.

In the prior art, there is a small and medium-low power X-ray generating device. The device integrates a pulsed high-voltage power supply with an X-ray generating component as shown in Figure 1A and Figure 1B. The electron beam is focused by the magnetic field generated by the transformer. Including low voltage power supply and control circuit 201, glass vacuum chamber 213, X-ray generating anode 203, X-ray generating cathode 204, transformer primary coil 211, first secondary coil 205, cylindrical transformer core 206, first rectifier diode 207 and the first coupling capacitor 208 .

The entire device is powered by a low-voltage DC power supply of 12 to 24 volts or a battery. The low-voltage power supply and control circuit 201 generate a high-frequency signal equal to the resonant frequency of the transformer, which is 72 kHz in this embodiment. Inside the low-voltage power supply and control circuit 201, the high-frequency signal controls the switching of the power supply through the H-shaped full-bridge circuit composed of semiconductor field effect transistors to generate high-frequency, low-voltage and large current to supply power to the transformer. The low-voltage power supply and control circuit 201 are placed outside the glass vacuum chamber 213 and are connected to the primary coil of the transformer in the glass vacuum chamber 213 through lead wires.

The X-ray generating cathode 204 based on field emission adopts an array of carbon nanotubes arranged vertically. 10 microns pitch. The X-ray generating cathode 204 based on field emission is composed of more than 8,000 carbon nanotubes, and the effective area of the X-ray generating cathode 204 based on field emission is about 0.8 square millimeters. Provides pulsed field emission currents in excess of 20 mA. The anode 203 of the X-ray generating portion may be a metal with high atomic weight such as tungsten, molybdenum, and gold, or a metal with high thermal conductivity such as copper and silver. High atomic weight metals can also be embedded into high thermal conductivity anodes as targets to increase X-ray production and improve heat dissipation. The X-ray generating anode is made into a thin cylinder and placed in the center of the cylindrical transformer core 206, because in this embodiment, the magnetic flux density at the center of the cylindrical transformer core 213 is the largest, and the best focusing can be achieved Effect. The cross-sectional area of the X-ray generating anode 204 should be as small as possible to avoid anode heating caused by eddy currents.

The device has the advantages of simple structure, reliable performance and long service life. However, the X-ray generating device needs to cooperate with the vacuum ion pump in the actual use process, and the existing technology cannot integrate the X-ray generating device and the vacuum ion pump, so that the X-ray generating device and the vacuum ion pump are required in the actual use process. Each pump requires its own power supply equipment, which makes it occupy a large area and is inconvenient to use.

SUMMARY OF THE INVENTION

Therefore, the technical problem to be solved by the present invention is to overcome the need for two power supply devices during use of the X-ray generating device and the vacuum ion pump in the prior art, which occupies an excessively large area and is inconvenient.

To this end, an X-ray tube with an integrated ion pump is provided, including a power supply unit, an ion pump module and an X-ray module;

The power supply unit includes a low-voltage power supply, and the low-voltage power supply is connected to a primary coil of a transformer;

The X-ray module includes an X-ray generating anode and an X-ray generating cathode, and the X-ray generating anode and the X-ray generating cathode are connected to both ends of the first secondary coil of the transformer through a first coupling circuit;

The ion pump module includes an ion pump anode and an ion pump cathode arranged vertically, and the ion pump anode and the ion pump cathode are connected to both ends of the second secondary coil of the transformer through a second coupling circuit.

further,

A first rectifier diode is arranged in parallel with the X-ray generating anode and the X-ray generating cathode.

further,

A second rectifier diode is arranged in parallel with the anode of the ion pump and the cathode of the ion pump.

further,

The X-ray generating anode is connected to the first secondary coil through a first coupling capacitor

The first rectifier diode (207) and the one coupling capacitor (208) form a first coupling circuit.

further,

the ion pump cathode is connected to the second secondary coil through a second coupling capacitor;

The second rectifier diode (211) and the second coupling capacitor (212) form a second coupling circuit.

further,

Both sides of the ion pump cathode are provided with ion pump magnets.

further,

The power supply unit, the ion pump module and the X-ray module are respectively arranged in a glass vacuum chamber;

The X-ray module is arranged on the upper part of the glass vacuum chamber;

The power supply unit is arranged in the middle of the glass vacuum chamber;

The ion pump module is located in the lower part of the glass vacuum chamber.

further,

The transformer further includes a cylindrical transformer core, and the cylindrical transformer core is disposed inside the primary coil, the first secondary coil and the second secondary coil, respectively.

The technical scheme of the present invention has the following advantages:

1. The high-voltage power supply of the vacuum ion pump is integrated with the high-voltage power supply of the X-ray source, so that the X-ray tube of the integrated ion pump provided by the present invention has the advantages of small size, light weight, simple structure and long life.

Description of drawings

In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the accompanying drawings required in the description of the specific embodiments or the prior art. Obviously, the accompanying drawings in the following description The drawings are some embodiments of the present invention. For those of ordinary skill in the art, other drawings can also be obtained from these drawings without creative efforts.

1A is a schematic diagram of a circuit structure of an X-ray generating device in the prior art;

1B is a schematic diagram of a circuit structure of an X-ray generating device in the prior art;

2A is a schematic diagram of the circuit structure of an X-ray tube with an integrated ion pump;

FIG. 2B is a schematic diagram of the mechanical structure of an X-ray tube with an integrated ion pump.

201, low voltage power supply; 202, primary coil; 203, X-ray generating anode; 204, X-ray generating cathode; 205, first secondary coil; 206, cylindrical transformer core; 207, first rectifier diode; 208, 209, ion pump anode; 210, ion pump cathode; 211, second rectifier diode; 212, second coupling capacitor; 213, glass vacuum chamber; 214, second secondary coil; 215, ion pump magnet .

Detailed ways

The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are a part of the embodiments of the present invention, but not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. The indicated orientation or positional relationship is based on the orientation or positional relationship shown in the accompanying drawings, which is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the indicated device or element must have a specific orientation or a specific orientation. construction and operation, and therefore should not be construed as limiting the invention. Furthermore, the terms "first", "second", and "third" are used for descriptive purposes only and should not be construed to indicate or imply relative importance. In addition, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

An X-ray tube with integrated ion pump, as shown in Figures 1 and 2, includes a power supply unit, an ion pump module and an X-ray module, the power supply unit includes a low-voltage power supply 201, and the low-voltage power supply 201 is connected to a primary coil 202 of a transformer , the X-ray module includes an X-ray generating anode 203 and an X-ray generating cathode 204, the X-ray generating anode 203 and the X-ray generating cathode 204 are respectively connected to both ends of the first secondary coil 205 of the transformer, and the ion pump module It includes an ion pump anode 209 and an ion pump cathode 210 arranged vertically, and the ion pump anode 209 and the ion pump cathode 210 are respectively connected to both ends of the second secondary coil 214 of the book transformer.

The effective effect of the present invention is that the ion pump module and the X-ray module are powered by a low-voltage power supply 201, and a primary coil 202 and two secondary coils are provided to achieve the purpose of supplying power to the ion pump module and the X-ray module respectively. And the two secondary coils have different resonant frequencies. By applying alternating currents of different frequencies to the primary coil 202, the device can work in any one or more of the ion pump module and the X-ray module. The two frequencies are calculated to avoid crosstalk with each other.

Usually, when the device is working in the ion pump module, the frequency of the input signal is the resonant frequency of the ion pump coil, which is used to maintain the vacuum degree in the vacuum chamber. When the X-ray emission module needs to work, the frequency of the input signal is the resonance frequency of the X-ray coil, the ion pump module stops working, and the X-ray module module starts to work to emit X-rays.

In one embodiment, a first rectifier diode 207 is arranged in parallel with the X-ray generating anode 203 and the X-ray generating cathode 204 . A second rectifier diode 211 is arranged in parallel with the ion pump anode 209 and the ion pump cathode 210 . By setting the first rectifier diode 207 and the second rectifier diode 211, the X-ray module module and the ion pump module can obtain relatively stable voltage or current.

In one embodiment, the X-ray generating anode 203 is connected to the first secondary coil 205 through a first coupling capacitor 208 . The ion pump cathode 210 is connected to the first secondary coil 205 through the second coupling capacitor 212 . By setting the first coupling capacitor 208 and the second coupling capacitor 212, the X-ray module module and the ion pump module can obtain relatively stable voltage or current.

In one embodiment, two sides of the ion pump cathode 210 are provided with ion pump magnets 215 for generating a magnetic field at the ion pump module to make the ion pump module work normally.

In one embodiment, the power supply unit, the ion pump module and the X-ray module are respectively arranged in a glass vacuum chamber 213 , the X-ray module is arranged in the upper part of the glass vacuum chamber 213 , and the power supply unit is arranged in the middle of the glass vacuum chamber 213 , the ion pump module is located in the lower part of the glass vacuum chamber 213 . The ion pump module and the X-ray module are respectively powered by the power supply unit arranged in the middle. The transformer further includes a cylindrical transformer core 206 disposed inside the primary coil 202 , the first secondary coil 205 and the second secondary coil 214 , respectively.

Obviously, the above-mentioned embodiments are only examples for clear description, and are not intended to limit the implementation manner. For those of ordinary skill in the art, changes or modifications in other different forms can also be made on the basis of the above description. There is no need and cannot be exhaustive of all implementations here. And the obvious changes or changes derived from this are still within the protection scope of the present invention.

Claims (8)

1. an X-ray tube integrating ion pump, is characterized in that, comprises power supply unit, ion pump module and X-ray module; The power supply unit includes a low-voltage power supply (201), and the low-voltage power supply (201) is connected to a primary coil (202) of a transformer; The X-ray module includes an X-ray generating anode (203) and an X-ray generating cathode (204), and the X-ray generating anode (203) and the X-ray generating cathode (204) are connected to the first coupling circuit with the first coupling circuit of the transformer. Both ends of the primary coil (205) are connected; The ion pump module comprises a vertically arranged ion pump anode (209) and an ion pump cathode (210), the ion pump anode (209) and the ion pump cathode (210) are connected to the second coupling circuit of the transformer through a second coupling circuit. Both ends of the secondary coil (214) are connected. 2. The X-ray tube with integrated ion pump according to claim 1, wherein, A first rectifier diode (207) is arranged in parallel with the X-ray generating anode (203) and the X-ray generating cathode (204). 3. The X-ray tube with integrated ion pump according to claim 1, wherein, A second rectifier diode (211) is arranged in parallel with the ion pump anode (209) and the ion pump cathode (210). 4. The X-ray tube with integrated ion pump according to claim 2, wherein, The X-ray generating anode (203) is connected to the first secondary coil (205) through a first coupling capacitor (208); The first rectifier diode (207) and the one coupling capacitor (208) form a first coupling circuit. 5. The X-ray tube with integrated ion pump according to claim 3, wherein, The ion pump cathode (210) is connected to the second secondary coil (214) through a second coupling capacitor (212); The second rectifier diode (211) and the second coupling capacitor (212) form a second coupling circuit. 6. The X-ray tube with integrated ion pump according to claim 1, wherein, Two sides of the ion pump cathode (210) are provided with ion pump magnets (215). 7. The X-ray tube with integrated ion pump according to any one of claims 1 to 6, characterized in that, The power supply unit, the ion pump module and the X-ray module are respectively arranged in a glass vacuum chamber (213); The X-ray module is arranged on the upper part of the glass vacuum chamber (213); The power supply unit is arranged in the middle of the glass vacuum chamber (213); The ion pump module is arranged at the lower part of the glass vacuum chamber (213). 8. The X-ray tube with integrated ion pump according to claim 7, wherein, The transformer further comprises a cylindrical transformer core (206), wherein the cylindrical transformer core (206) is located at the primary coil (202), the first secondary coil (205) and the second secondary coil, respectively (214) internal settings.

Images