A well-type ionization chamber for measuring radioactive source activity

Abstract

The present disclosure seeks to protect a well-type ionization chamber for measuring radioactive source activity. The chamber comprises an ionization chamber housing and a positioning structure, the positioning structure comprising a positioning block and a connecting wire, wherein one end of the connecting wire is connected to the positioning block and the other end is connected to the inner wall of the ionization chamber; the positioning block also comprises an electromagnetic generator capable of generating different magnetic polarities; the ionization chamber housing comprises an upper cover and a body, wherein the body comprises a vertical wall and a bottom shell; the ionization chamber also comprises a positioning post, which comprises a permanent magnet; the positioning structure has two states: a clamped state and a relaxed state. In the clamped state, the electromagnetic generator generates a magnetic polarity opposite to that of the permanent magnet; in the relaxed state, the electromagnetic generator generates a magnetic polarity identical to that of the permanent magnet. The present ionization chamber can accurately position a bracket.

Description

Technical Field

[0001] The invention relates to a well-type ionization chamber for measuring radioactive source activity. Background Art

[0002] A well-type ionization chamber is a device that uses the principle of thermoluminescence to measure nuclear radiation. Thermoluminescent elements are solids with a crystalline structure that often contain various lattice defects (such as missing atoms or ions or the addition of certain foreign impurities). These defects attract oppositely charged particles, forming "traps." When exposed to radiation, electrons and positive ions generated in the solid are captured by the traps. During testing, the solid is heated, and the released electrons and positive ions recombine with oppositely charged particles elsewhere in the solid, emitting light. This emitted light passes through and is directed to a photomultiplier tube, generating a photocurrent. This current is then amplified by a DC amplifier and recorded by a recorder. By measuring the magnitude of this current, the amount of radiation received by the thermoluminescent element can be determined.

[0003] A stent containing radioactive material and a phantom simulating human tissue are placed in a well-type ionization chamber, and a thermoluminescent element is placed in the phantom. The thermoluminescent element records the radiation of the radioactive material. By analyzing the amount of radiation received by the thermoluminescent element, the amount of radiation received by the phantom from the stent containing radioactive material can be calculated. Summary of the Invention

[0004] The object of the present invention is to provide a well-type ionization chamber for measuring the activity of a radioactive source.

[0005] A well-type ionization chamber for measuring radioactive source activity is characterized in that: the ionization chamber includes an ionization chamber shell and a positioning structure, the positioning structure includes a positioning block and a connecting wire, wherein one end of the connecting wire is connected to the positioning block and the other end is connected to the inner wall of the ionization chamber; the positioning block also includes an electromagnetic generator, which can generate different magnetic poles; the ionization chamber shell includes an upper cover and a body, and the body includes a vertical wall and a bottom shell; the ionization chamber also includes a positioning post, which includes a permanent magnet block; the positioning structure has two states, a clamped state and a relaxed state. In the clamped state, the electromagnetic generator generates a magnetic pole opposite to that of the permanent magnet block; in the relaxed state, the electromagnetic generator generates a magnetic pole identical to that of the permanent magnet block.

[0006] Optionally, the ionization chamber also includes a control module, a control panel and a power supply. The control module is connected to the electromagnetic generator of the positioning block via a connecting line, the power supply is connected to the control module, and the control panel is connected to the control module. The control panel is arranged on the outside of the ionization chamber shell.

[0007] Optionally, the ionization chamber further includes a nut, and the nut includes a shaft sleeve and a positioning plate.

[0008] Optionally, a positioning plate is located at one end of the nut and is used to position the bracket. The inner side of the sleeve has an internal thread and the outer side has an external thread. The positioning column has an external thread. The inner thread of the sleeve cooperates with the external thread of the positioning column, and the external thread of the sleeve cooperates with the upper cover of the ionization chamber shell.

[0009] Optionally, the number of the positioning structures is more than 3.

[0010] Optionally, the positioning line includes a guide wire and a fixing line.

[0011] Optionally, the positioning line and the conducting wire are an integrated structure and have equal lengths.

[0012] Optionally, the positioning line and the conducting wire are separate structures, and the length of the positioning line is shorter than the length of the conducting wire.

[0013] Optionally, a shell guide portion is provided on the bottom shell, and a positioning block guide portion is provided on the positioning block, and the shell block guide portion and the positioning block guide portion are concave-convex matched.

[0014] Optionally, a radial protrusion is provided on an inner side of the vertical wall of the ionization chamber, and the radial protrusion is used to support the phantom. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 Well-type ionization chamber

[0016] Figure 2 for Figure 1 AA-direction cross-section view clamped state

[0017] Figure 3 for Figure 1 Relaxed state of the AA cross-section in

[0018] Figure 4 for Figure 2 Middle section B

[0019] Figure 5 This is the electrical connection diagram of the well-type ionization chamber

[0020] Figure 6 for Figure 2 Another embodiment of

[0021] Figure 7 for Figure 2 Another embodiment of DETAILED DESCRIPTION

[0022] A well-type ionization chamber is a device that uses thermoluminescence to measure nuclear radiation. During use, the stent and phantom must be precisely positioned to accurately simulate the stent's positional relationship with the human body. Because well-type ionization chambers typically have a relatively deep vertical depth, precise positioning of the stent is difficult to achieve based solely on operator experience. Therefore, a more precise stent placement and fixation device is required.

[0023] The stent disclosed herein is generally a stent 200 with radioactive material, which may be iodine 131 or the like.

[0024] See attached Figure 1-3 The well-type ionization chamber 100 of the present disclosure includes ionization chamber housings 1 and 2 and a positioning structure 5. The positioning structure 5 includes a positioning block 52 and a connecting wire 51, wherein one end of the connecting wire 51 is connected to the positioning block and the other end is connected to the inner wall of the ionization chamber. The positioning block 52 also includes an electromagnetic generator 54 capable of generating magnetic poles. The ionization chamber also includes a positioning column 3, which includes a permanent magnet block 32. The positioning structure has at least two states, including a clamped state and a relaxed state. In the clamped state, the positioning block 52 clamps the bracket; in the relaxed state, the positioning block 52 relaxes the bracket.

[0025] Advantageously, the bracket can be better positioned by changing the state of the positioning structure, thereby avoiding errors caused by human operation.

[0026] Optionally, the electromagnetic generator 54 has a power-on state and a power-off state. In the power-on state, the magnetic pole of the electromagnetic generator 54 is the north pole or the south pole.

[0027] The advantage is that like magnetic poles repel each other and unlike magnetic poles attract each other. By giving the electromagnetic generator different magnetic poles, the positioning structure can be placed in a clamped state and a relaxed state, which is easy to control.

[0028] Optionally, when the bracket is not placed in the ionization chamber, the electromagnetic generator is in a power-off state and the positioning structure is in a relaxed state;

[0029] After the bracket is placed in the ionization chamber, the electromagnetic generator is powered on. The generated magnetic poles of the electromagnetic generator are opposite to those of the permanent magnet block 32. Due to the attraction between opposite poles, the positioning block 52, driven by the electromagnetic generator, moves toward the permanent magnet block 32. As the positioning block 52 moves, it pushes the bracket to move and clamps the bracket 200, placing the positioning structure in a clamped state. After the bracket is clamped, the electromagnetic generator is powered off.

[0030] Before the stent is removed, the electromagnetic generator is powered on. The magnetic poles generated by the electromagnetic generator match those of the permanent magnet 32. Since like poles repel, the positioning block 52, driven by the electromagnetic generator 54, moves in the direction opposite to the permanent magnet 32. As the positioning block 52 moves, it no longer clamps the stent, releasing the positioning mechanism and allowing the stent to be removed. After the stent is released, the electromagnetic generator is powered off.

[0031] Optionally, the electromagnetic generator is not powered before the stent is removed.

[0032] Advantageously, after the electromagnetic generator is powered on, the bracket is in a clamped state or a relaxed state, and there is no need to power the electromagnetic generator again to save energy. At the same time, when in the clamped state, timely power off is also helpful to prevent the bracket from being deformed due to the clamping force.

[0033] Optionally, the ionization chamber further includes a control module 6 and a power supply 7. The power supply 7 is connected to the control module 6, which is in turn connected to an electromagnetic generator 54 via a connecting line 51. The control module 6 controls the electromagnetic generator 54 to generate an N-pole or an S-pole. When the magnetic poles of the electromagnetic generator 54 align with those of the permanent magnet 32, the electromagnetic generator 54 drives the positioning block 52 away from the permanent magnet 32, thereby loosening the bracket. When the magnetic poles of the electromagnetic generator 54 align with those of the permanent magnet 32, the electromagnetic generator 54 drives the positioning block 52 toward the permanent magnet, thereby clamping the bracket.

[0034] Advantageously, by arranging components such as the power supply inside the ionization chamber housing, the structure is simplified.

[0035] Optionally, the connecting line 51 includes a conductive wire 511 and a fixing wire 512. Optionally, the conductive wire 511 and the fixing wire 512 are integrated and have the same length.

[0036] Optional, see Figure 6 and 7 Wire 511 and fixing wire 512 are separate components, and the length of wire 511 is equal to or greater than the length of fixing wire 512. Wire 511 connects control module 6 and electromagnetic generator 54. Fixing wire 512 connects fixing block 52 and the inner wall of the ionization chamber housing. Wire 511 and fixing wire 512 can be fixed to the same point on the inner wall of the ionization chamber housing, or they can be fixed to different points on the inner wall of the ionization chamber housing.

[0037] Optionally, there are three, four, or more connecting wires 51. The connecting wires 51 are axially arranged on the inner wall of the ionization chamber housing. When the bracket is in the clamped state, the connecting block 52 connected by the connecting wires 51 is located circumferentially of the bracket, and the connecting block 52 positions and secures the bracket 200.

[0038] Advantageously, the integrated connection line simplifies the structure, but the wire may have poor contact due to connection problems, affecting the use of the device. The connection line is set as a split structure and set at different connection points to reduce coupling failure between different components.

[0039] Optionally, the length L of the connecting wire 51 or the fixing wire 512 is equal to the radius R1 of the inner wall of the ionization chamber body minus the radius R2 of the bracket 200 .

[0040] Optionally, the ionization chamber includes an upper cover 1 and a main body 2, wherein the main body 2 includes a bottom shell 22 and a vertical wall 21. A radiation phantom 300 and a positioning structure 5 are disposed within the enclosed space enclosed by the upper cover 1 and the main body 2. During testing, the bracket 300 is positioned within the enclosed space of the ionization chamber. The ionization chamber also includes a positioning post 3, the lower portion of which includes a permanent magnet 32. A nut 4 is disposed on the outer side of the positioning post 3, and the nut 4 includes a sleeve 43 and a positioning plate 42. The positioning plate can secure the bracket 300 from one side after it is positioned. The vertical wall 21 also has a radial protrusion 212 on the inner side to support the phantom 300.

[0041] Optionally, the outer side of the positioning column 3 has an external thread, and the inner side of the shaft sleeve 43 has an internal thread. By rotating the shaft sleeve 43, the position of the positioning plate 42 is adjusted, and the bracket 200 is fixed by the positioning plate 42.

[0042] Optionally, the outer side of the sleeve 43 is an optical axis. The optical axis passes through the hole 11 provided in the upper cover 1. Further optionally, the outer side of the sleeve 43 has an external thread, and the hole 11 has an internal thread. By rotating the sleeve 43, the sleeve 43 moves in the hole 11, thereby raising or lowering the height of the positioning plate 42.

[0043] Advantageously, the bracket can be easily adjusted in the axial direction by adjusting the shaft sleeve 43 .

[0044] Optionally, the control module 6 and the power supply 7 are located inside the body 2 .

[0045] Optionally, the ionization chamber further comprises a control panel, which is arranged on the outer wall of the ionization chamber and is connected to the control module for inputting instructions for controlling the electromagnetic generator.

[0046] See attached Figure 4 Optionally, a housing guide is provided on the upper surface of the bottom housing 22, and the positioning block 52 has a positioning block guide. The housing guide cooperates with the positioning block guide, allowing the positioning block 52 to move along a set path on the upper surface of the bottom housing 22. Furthermore, the housing guide may be a groove 221, and the positioning block guide may be a guide rib 53. The guide rib 53 cooperates with the groove 221, so that when the positioning block 52 moves, the guide rib 53 moves within the groove 221. Furthermore, the housing guide may be a guide rib, and the positioning block guide may be a groove.

[0047] See attached Figure 5 Optionally, when powered, the electromagnetic generator 54 of the positioning block 52 can generate magnetic poles that are the same as or opposite to those of the permanent magnet 32, thereby generating an attractive or repulsive force F. This attractive force drives the positioning block 52 toward or away from the permanent magnet 32, thereby positioning, clamping, or loosening the bracket 200. The control module 6 controls the electromagnetic generator 54 to generate magnetic poles. The power supply 7 supplies power to the control module 6.

[0048] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art will be able to modify the technical solutions described in the aforementioned embodiments or replace some of the technical features therein with equivalents. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included within the scope of protection of the present invention.

Claims

1. A well-type ionization chamber for measuring radioactive source activity, characterized in that: The ionization chamber includes an ionization chamber housing and a positioning structure. The positioning structure includes a positioning block and a connecting wire, wherein one end of the connecting wire is connected to the positioning block and the other end is connected to the inner wall of the ionization chamber; the connecting wire includes a conductor and a fixing wire; The positioning block also includes an electromagnetic generator capable of generating different magnetic poles; The ionization chamber housing includes an upper cover and a body, and the body includes a vertical wall and a bottom shell; The ionization chamber further includes a positioning post, which includes a permanent magnet block; The positioning structure has two states, a clamping state and a loosening state. In the clamping state, the electromagnetic generator generates a magnetic pole opposite to that of the permanent magnet block. In the relaxed state, the electromagnetic generator produces the same magnetic poles as the permanent magnet block.

2. A well-type ionization chamber for measuring radioactive source activity according to claim 1, characterized in that: The ionization chamber also includes a control module, a control panel and a power supply. The control module is connected to the electromagnetic generator of the positioning block through a connecting line, the power supply is connected to the control module, and the control panel is connected to the control module. The control panel is arranged on the outside of the ionization chamber shell.

3. The well-type ionization chamber for measuring radioactive source activity according to claim 1, wherein: The ionization chamber further comprises a nut, which comprises a shaft sleeve and a positioning disk.

4. A well-type ionization chamber for measuring radioactive source activity according to claim 3, characterized in that: The positioning plate is located at one end of the nut and is used to position the bracket. The inner side of the sleeve has an internal thread and the outer side has an external thread. The positioning column has an external thread. The inner thread of the sleeve cooperates with the external thread of the positioning column, and the external thread of the sleeve cooperates with the upper cover of the ionization chamber shell. 5 . The well-type ionization chamber for measuring radioactive source activity according to claim 4 , wherein the number of the positioning structures is three or more.

6. The well-type ionization chamber for measuring radioactive source activity according to claim 1, wherein the connecting wire and the conducting wire are an integrated structure and have the same length.

7. A well-type ionization chamber for measuring radioactive source activity according to claim 6, wherein the connecting wire and the conducting wire are separate structures, and the length of the connecting wire is shorter than the length of the conducting wire.

8. A well-type ionization chamber for measuring radioactive source activity according to claim 7, wherein the bottom shell is provided with a shell guide portion, and the positioning block is provided with a positioning block guide portion, and the shell guide portion and the positioning block guide portion are concave-convex matched.

9. A well-type ionization chamber for measuring radioactive source activity according to claim 7 or 8, wherein a radial protrusion is provided on the inner side of the vertical wall of the ionization chamber, and the radial protrusion is used to support a phantom.

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