JPH01503404A - Exploration device inside the cylinder and exploration system equipped with this device - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] An exploration device for the inside of a cylindrical body and an exploration system equipped with this device. Seki (Service National des Champs Intense This is the result of joint research with Mr. S＞ (Representative Guy Aubert), and it It concerns the exploration device inside the cut.

The invention can be applied in particular to the field of medicine, where the magnet is based on nuclear magnetic resonance. used to form images. However, the present invention can be used in other fields, in particular in other cylindrical molds. Applications are also possible in other technical fields where gunnets and cylindrical bodies are used.

To form a nuclear magnetic resonance image, a continuous and powerful beam generated using a magnet is required. It is necessary to place the body whose section is to be imaged into a uniform magnetic field.

In order to improve the uniformity of magnets, we must know the non-uniformity.

Magnet inhomogeneity describes the value of the generated magnetic field at different locations in the space involved. It is measured by recording. To do this, move the probe to these different positions. move it. This related space is then explored. Especially forming nuclear magnetic resonance images To do this, the magnetic field is uniform on the order of parts per million (ppm). It is known that there is a need. Therefore, the position in the internal space where the value of the magnetic field is recorded is The position must be determined with the highest possible precision geometrically. In addition, magnetic field compensation It may be necessary to repeat the measurement at the same position on the magnet after making a positive measurement.

Therefore, it is necessary to have a device that is not only accurate but also easy to handle. lastly, Data regarding the magnetic field generated using a magnet can record the value of the magnetic field. The more points that are made, the more detailed they are, so the exploration device is not easy to use. Must not be too expensive.

The present invention provides an exploration device that can completely solve all of the above problems. do. For handling and installation, this device must be installed inside the cylinder to be probed. and a frame having means for fixing and adjusting the. Once the frame In the positioned state, the device moves in translation parallel to the axis of the cylinder and It also has a probe holder that can rotate around this axis. . Finally, for simplicity, the probe holder accurately accommodates the measuring probe. Comes with multiple pre-cut housings. Therefore, the total The axis of the cylinder is selected from among the points inside the cylinder. All points with the same distance to the will be explored. Additionally, the probe position can be changed from one housing to another. By varying all desired radial distances are explored. multiple housings Place multiple probes simultaneously within the ring and switch probes manually or electronically. It is also possible to search the corresponding radial distance by checking.

The present invention is an apparatus for exploring the inside of a cylindrical body, which includes a frame functioning as a support. , means for fixedly adjusting the position of the frame within the cylinder, and a probe holder; a sliding means for sliding the probe holder along the axis of the cylinder; and a sliding means for sliding the probe holder along the axis of the cylinder; and a rotation means for rotating the holder around the axis of the cylindrical body, the probe holder is The probe is characterized in that it has a predetermined housing for accommodating the measuring probe. It relates to a device that is used as a sign.

The invention can be better understood by reading the following description with reference to the accompanying drawings. Let's come. The drawings are merely examples and do not limit the invention. In each drawing , the size and scale of the various elements are not exact. But the same reference number means the same element represents.

FIG. 1a is a perspective view of the device of the invention, showing the sliding means of the probe holder and the probe. The holder itself is shown.

FIG. 1b is a perspective view of the pivoting means of the probe holder.

FIG. 2 is a schematic perspective view of the frame fixing means.

Figures 1a and 1b are diagrams of the exploration device of the invention. The interior space 1 to be explored is It is illustrated as a cylinder with a generatrix 2 and a circular cross section 3. This exploration device The system is equipped with a system, the components of which are designated with reference numbers 4-24. This frame The frame includes a slider 4 as a main component. This slider is is supported by two sets of spacers 5.6 having three spacers. three Each set of spacers is arranged in a different plane approximately perpendicular to the axis 7 of the cylinder. is located.

- For example, two planes are approximately 30 cm apart. In each plane, the spacer is They are oriented at an angle of approximately 120° to each other.

In the perspective view of Figure 1a, one of the spacers in each plane is This is omitted. Figure 2 shows the positions of spacers 8 and 9 shown in figure ``a'' and FIG. 1a briefly shows the position of the spacer 10, which is not shown. child These spacers have one end formed by any means, in particular opening 12 and spacer 8. and 10 by a pentagonal member 11 with two faces 13.14 serving as the base of the is fixed to the slider 4. The opening 12 accommodates translational movement of the probe holder. Helpful.

Each of the six spacers of the frame is equipped with a disk-shaped adjustment knob 15. . One face of each knob is fitted with a nut 17 fixed to the frame (member 11). A protrusion 16 with a male thread is provided on the other side, and a smooth circular protrusion 16 is provided on the other side. A columnar protrusion 18 is provided. The protrusion 18 is formed on the bottom of the spacer member 19. It is provided to fit into the hole made. Each spacer member further includes a head It is equipped with a smooth cylindrical protrusion 20. Each spacer member has a different length. can be inserted into each other and preformed to form a larger spacer. . For this reason, the diameter of the spacer protrusion 820 is smaller than the hole provided at its bottom. consistent with the diameter of When installing this exploration device inside a cylindrical body, use a spacer. A protrusion 20 is provided on the head of the unit so as to fit into the unit landing member, for example 21. do. Each landing member accommodates two spacers, e.g. 9.19 protrusions, on the surface. two holes located parallel to each other but on different planes 5 or 6 for For example, it has 22.23. On the other side of the implantation member, these implantation members are Shoes made of plastic material to prevent damage to the inner surface of the cylinder 1, e.g. For example, 24 is attached.

By adjusting all knobs of all spacers, fixing the frame to cylinder 1 is the same. At times, the position of this frame may be adjusted to ensure that the probe holder 25 is accurately cylindrical. 1 to be able to rotate around the axis 7. between the hole in the landing member and the bottom of the spacer. The hole is slightly wider than the protrusion, so this mechanical play makes this adjustment possible. becomes easier. By supporting the inner wall of the cylindrical body in this way, the device of the present invention solves all the problems of fixing a cylinder on a support.

The exploration device further includes sliding means for the probe holder 25. This sliding The means comprises as a main component a shaft 26 with a polygonal cross section. child Here the cross section can even be square. The shaft 26 has a shoe, e.g. or 28 (FIG. 1b) to rest on the slider 4 without friction. These shoes A predetermined number of them are distributed along each support surface of the slider 4, for example. shuff When the probe moves forward and the cantilever length of the probe holder 25 increases, the roller pair 29 ．． 30 and 31.32 exert a reaction on the upper surface of the shaft 26. The shaft of the roller is It is fixedly supported by the lid. This reaction prevents the shaft 26 from swinging. will be stopped. The cross section of the shaft 26 is oriented relative to the position of the abscissa of the shaft 26. A scale 33 with graduations is fixed on the opposite side from the one shown in FIG. This scale The scale 33 has a glass beam with grooves cut at regular intervals. . The groove exits in front of the optical encoder 34 as the shaft 26 slides. optical encoder The encoder 34 is provided with a groove, and when this optical encoder 34 is used, the shaft The abscissa of the tip of the drum 36 can be measured and displayed on the display device 35. It is possible, for example, to provide The crank 37 is approximately perpendicular to the axis 7, and the slider 4 can be rotated about an axis 38. wire 3 9 or the cable is wrapped around the drum 36 several times. This wire is One end is pulled to a stopper 40 fixed to the shaft 26 near the probe holder 25. The other end is fixed to the indexing hub 42 by a tension adjustment screw 41. ing. This hub is also fixed to the shaft 26 at its other end. crank 3 By operating 7, the shaft 26 is slid. This sliding is caused by stopper 4 0 or stopped on either side when the indexing hub 42 comes into contact with the slider 4. Ru.

In a preferred embodiment, means for rotating the probe holder 25 about the axis 7 is a mandrel that is free to rotate internally and is attached on the axis of the shaft 26. The main component is a rail 43 (FIGS. 1a and 1b). This mandre The lever 43 is for accommodating the claw 45 of the indexing knob 46 at the rear end (Fig. 1b). A longitudinal recess 44 is provided. The indexing knob has one or more protrusions. 47 and a ring sliding around the mandrel 43. Ru. The protrusion 47 is fitted into a socket 48 provided at an opposite position on the indexing hub. It is provided for the purpose of The socket 48 is circular about the axis 7 of the indexing hub. The shapes are regularly distributed over this indexing hub. The hub 42 may be screws 49.50, which fit into holes 51.52 in hub 42, respectively. It is fixed to the end of the shaft 26. Once this hub is secured, turn knob 46 backwards. By pulling it, the claw 45 slides within the recess 44. Next, place the mandrel 43. Rotate the desired angle and push the knob 46 forward to move the protrusion 47 into the preselected position. 48. As a result, at the other end, the probe holder 25 is aligned with the axis 7. and is maintained at a predetermined angle of rotation.

This angle corresponds to a multiple of the angular spacing of two adjacent sockets 48 on the hub 42. are doing. Therefore, the sockets 480 are spaced apart from each other by an angle equal to the angular pitch. The cylinder 1 can be probed along several radial directions. This angular pitch is sufficient If it is not fine or there is another reason, remove screws 49 and 50 and screw the hub 42. After rotating the holes 53.5 located on the same side as the previous holes 51.52 respectively By reinstalling these screws through 4, the hub 42 is shifted by a predetermined angle. Is possible. The angular pitch between holes 51 and 53 and holes 52 and 54 is Preferably, the angular pitch of the sockets 48 is complementary. Also, encoder, e.g. For example, it is also possible to encode the rotation of the mandrel 43 using an optical encoder. be.

Encoders are commercially available in many configurations.

Probe holder 25 is attached to the end of mandrel 43. probe ho The router comprises a series of radially regularly distributed housings 55-61. . The housing 55 is located on the axis 7. Pit of distribution of housings 55-61 If the pitch is not fine enough, use the first Housings 62 to 66 of a different series radially shifted from the housing of the series It is possible to provide However, this other series has the same diameter as the first series. It is also possible to adapt the exploration to potentially different distributions of directions.

All parts of the exploration device are manufactured from non-magnetic materials. In particular, the slider 4 and the shaft 26 is made of aluminum. Spacer set, landing member, drum, crank, mandrel DERLIN is a non-magnetic plastic material, especially the product name DERLIN. Preferably, it is made of materials known in the art. sliding shoes 27, 28 and rollers 29 ．． 32 is coated with polytetrafluoroethylene.

In order to use the exploration device of the present invention, first of all, a frame is installed inside the cylindrical body 1. Install. To adjust the position of this frame, do the following: crank 37 so that the stopper 40 hits the slider 4. At this position, Adjust spacer set 5, that is, the spacer set closest to the probe holder 25. Ru. A predetermined outer point of the probe holder 25 is moved away from the cylindrical body 1 by rotation. Coordination is complete when every equidistant position of can be occupied. This operation For simplicity, adjustments can be made by pressing shims inside the cylinder. can.

When the spacer set 5 is adjusted using the crank 37, the probe holder 25 is moved until the hub 42 collides with the other end of the slider 4. Here, the spacer Adjustments to spacer set 6 are made in the same manner as for set 5. As a general rule, the spacer There is no need to perform set 5 adjustments again. In fact, spacer set 5 was involved in the previous adjustment. The adjustment of spacer set 6 is the only method that is blind in this case, as long as it is the only set that It is. However, the probe holder must be repositioned to the appropriate position each time the entire operation is performed. It is possible to repeat Yu.

Considering the limits of cantilever deflection, an adjustment of spacer set 6 is carried out, while Preferably, the probe 66 is fitted into the housing of the probe holder 25.

Therefore, the weight of the probe 660 and the weight of the power supply cable 67 are It is considered as the additional deflection caused by the When using multiple probes, these Perform similar operations with multiple probes. The probe boulder 25 is the radial part If the probe holder 25 is circular, the probe holder 25 is circular. Preferably, the cable 67 is passed through the hole 68 to the rear of the device. child In order to change the position of the probe 66 within the housing, Ensure that no stress is applied to this probe. This installation requires operation and adjustment. Once the preparation is complete, the original use begins.

As a first step, an operator places the probe 66 into a predetermined housing.

The operator further engages the indexing knob 46 into position within the indexing hub 42. Ru. Next, the operator uses the crank 37 to move the device inside the cylinder 1 into the cylinder base. Move along the line. The operator places the measuring instrument 69 (main unit) at the predetermined abscissa position. In the example, the corresponding magnetic field value is measured using an NMR Gaussmeter. this The value may be stored in processor 70.

This value is written to restore 4 as necessary. Find all given abscissas of a generatrix. Once the operator has completed the inspection, the operator grasps the indexing knob 46 and pulls it backwards. is rotated by a predetermined angle with the mandrel 43. After fitting the knob, the different Repeat the measurement of the properties of the magnetic field with respect to the abscissa. In the same way, move the index knob to the Continue measuring until you return to the same position you originally occupied. Here the operator is a professional Grasp the tube 66 and place it into another housing. Then repeat all the above operations.

In order to move the probe 66, the operator applies an action from the other end of the cylinder 1. Boss.

To avoid having to move the probe 66, the probe holder 25 is It is possible to use multiple probes, each inserted into a housing, at the same time. It was. In this case, the measurement cables of these probes are controlled by the processor 70. The multiplexer 71 is connected to the multiplexer 71. The exploration method for this preferred working example is as follows: It is as follows. When the probe holder is oriented in the desired direction, the operator Move the probe holder to the predetermined horizontal coordinate. Once this given abscissa is reached, Processor 70 sends an enabling command to display device 35 . Next, the processor 70 The multiplexer 71 is controlled sequentially. Multiplexer 71 measures each probe in turn. connection to the fixture 69. Once the measurement results have been recorded, the processor 70 issues an authorization signal. The instruction lamp 72 of the display device 35 lights up.

The operator then moves the probe holder anew to reach another selected abscissa. reach. In the same manner, the processor 70 each time determines that the abscissa reached is the Make sure that it corresponds to the exact predetermined abscissa that you have previously memorized in the harpoon. . During the measurement, the operation of the crank 37 also follows the instruction lamp appearing on the display device 35. This can be prohibited by lighting the button 73. On the other hand, the abscissa If the adjustment is not accurate, the processor 70 may cause the indicator lamp 73 to blink, for example. can be done.

The translational and rotational movements of the probe holder 25 can be mechanized and Exploration can be automated under processor control. For mechanization, use a magnetic field Preferably, non-generating air means are utilized.

international search report 11′′藝＾“111i・KTE/FR87100193 International Investigation Report FR8700193 SA　17393

Claims (13)

[Claims] 1. Exploration device (Fig. 1a, Fig. 1b) inside the cylinder (1), comprising a support and a frame (4 to 24) that functions as a the means for adjusting (5, 6) and the probe holder (25); Sliding means (26 to 41) for sliding along the axis of the cylindrical body and this probe holder rotating means (42 to 54) for rotating the cylindrical body around the axis of the cylindrical body; The lobe holder has a predetermined housing for accommodating the measurement probe (66). (55 to 65). 2. The frame comprises two sets of three spacers (8, 9, 10). , each set of spacers is supported in the same plane perpendicular to the axis of the cylinder (11) and mutually arranged. The two planes form an angle of approximately 120° (Fig. 2), with one of the planes facing the frame. 2. Device according to claim 1, characterized in that it is located approximately at right angles to one end. 3. 3. The spacer according to claim 2, wherein the spacer is of a Modineal type (20). equipment. 4. The sliding means has a polygonal cross-section shaft (26) and a shaft (26) which is connected to the shaft without friction. The shaft is fixed to the frame above for support, and the profile is the cross-section of this shaft. 4. A slider according to claim 1, further comprising a slider (4) adapted to The device according to item 1. 5. Said sliding means are connected to the agitating drum (36) and to the wire wound around this drum. an ear (39), at least one end of which is connected to one end of the shaft. 5. A device according to claim 4, characterized in that the device is connected to 6. The sliding means comprises a crank (37) connected to the driving drum. 6. The device according to claim 5, characterized in that: 7. The rotation means is a circular shaft rotatably mounted inside a polygonal shaft. According to any one of claims 1 to 6, characterized in that it comprises a steering wheel (43). equipment. 8. Said rotation means cooperate with an indexing knob (46) supporting said mandrel. characterized in that it comprises an indexing hub (42) fixed to said shaft for the purpose of Apparatus according to claim 7. 9. The probe holder is attached to a flange (a first flange) fixed to one end of the mandrel. 9. The device according to any one of claims 1 to 8, characterized in that it comprises a). 10. comprising means (33, 34) for measuring translational movement of the probe holder; 10. A device according to any one of claims 1 to 9. 11. Claim 1, further comprising means for measuring rotation of the probe holder. 10. The device according to any one of 10 to 10. 12. Pneumatic pressure that causes translational and/or rotational movement of the probe holder 12. Device according to any one of claims 1 to 11, characterized in that it comprises a motor. 13. An exploration system comprising the device according to any one of claims 1 to 12. a plurality of probes each located within the housing of the probe holder; A system comprising measurement multiplexing means (70, 71) performed using these probes. stem.