JPH04256899A - Machine for replacing inspection-entrance door into area where radiation is cas and use of such machine - Google Patents

Abstract

PURPOSE: To provide a machine for exchanging an inspection entrance door to a region exposed to radioactive rays. CONSTITUTION: A machine 1 has an outer-surrounding body 1 with one opening 2 and shuttle systems 7, 8, and 10. A plate 15 for retaining an inspection entrance door 20 can be moved into or outside the opening. With the shuttle systems, a plate may be placed in front of the opening. Only one gasket system can maintain separation from the outside and can limit the emission of radioactive rays to the inside of the outer-surrounding body 1, thus easily eliminating contamination.

Description

[Detailed description of the invention]

0001

FIELD OF THE INVENTION The present invention relates to a machine for replacing inspection entrance doors to irradiated areas and the use of such a machine.

0002

[Prior Art] Such a machine is covered by French Patent No. 2
No. 544 542. This machine is designed to be operated from the outside and has one mouth that is mated to one opening on the bioprotective wall. The irradiated area is located behind the bioprotective barrier and in the second
It extends into a small room delimited by the walls of
This second wall is sealed but radiolucent and includes an examination entrance door to the irradiated area. These doors are often equipped with means that must be replaced periodically, such as sensors and, if gas is circulated within the chamber, an agitator. However, as soon as the test entrance door is removed, contamination products can flow out of the chamber. Machines for the replacement of said inspection entrance doors must therefore be equipped with the necessary sealing to prevent the escape of these contaminated products, and no communication can ever occur between the irradiated area and the outside world. must not.

[0003] Machines for such door replacement include a rotary shuttle mechanism having two door supports in the form of recesses with means for gripping the inspection entrance door. A first door support is placed in front of the opening in the bioprotective wall. The door to be removed is grabbed, removed and held in the recess. Rotation of the shuttle mechanism then allows a second door support with a replacement door accommodated in its recess to be moved in front of the opening in the bioprotective barrier. The replacement door is fed into the opening in the bioprotective wall until it reaches the wall of the chamber. This machine has to fulfill bioprotection and sealing functions, which makes it heavy and difficult to handle due to the large amount of radiation absorbing material that has to be placed around the shuttle mechanism. Become something.

The required sealing can only be obtained by using multiple gaskets or packings. However, these gaskets or packings do not provide complete safety. Finally, for use of the machine it is necessary that the chamber be provided with a sleeve for connecting the bioprotective wall opening to the opening of the chamber on which the door is placed. . In that case, an inspection entrance door is fixed to a rod extending inside the sleeve. Prior to use of the machine, the rod is withdrawn to slide the examination entrance door within the sleeve and into the vicinity of the bioprotective barrier. The rod is then removed from the inspection entrance door. Naturally, the inspection entrance door and the sleeve are constructed such that the seal is never broken.

However, such an overall structure is complex and expensive. Additionally, to avoid excessively long sleeves,
It may be necessary to locally deform the chamber to move the examination entrance door closer to the biological barrier.

[0006]

The aim of the machine according to the invention is therefore to avoid the above-mentioned complications in its installation and method. Its basic originality is that this novel machine is used between the bioprotective wall and the chamber wall. This machine no longer needs to perform a bioprotective function and simply needs to be sealed. Its sealing is much easier to ensure because its construction is much simpler and because the severity of the problems caused by slight defects in the sealing is smaller than in the case of machines used from the outside. It is possible to

In particular, currently used in the art,
It is possible to dispense with a multi-effect gasket or packing which is arranged around the opening of the bioprotective wall and whose special shape ensures non-contamination of the external area. In the case of the novel machine according to the invention, around the opening of said chamber, although slight contamination may occur,
Decontamination after the occurrence of contamination is sufficient to restore acceptable noncontamination.

[0008]

SUMMARY OF THE INVENTION The present invention therefore relates to a machine for replacing an inspection entrance door to a contaminated area.
an envelope having two openings and housing two door manipulation systems, each of said door manipulation systems having a door support and means for securing said door to said support. have,
The enclosure further comprises a shuttle mechanism configured such that the door supports are suspended below and each of the door supports can be positioned alternately within the opening. the machine forming a seal between the enclosure and a wall delimiting the contaminated area;
and a first gasket disposed about the opening, the machine further forming a seal between the envelope and the door support positioned within the opening. one second gasket disposed within the opening and one third gasket disposed on the support forming a seal between the door and the door support; and a device for decontaminating a sealed volume delimited by three gaskets.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The invention will now be explained in more detail with reference to non-limiting examples and the accompanying drawings, in which: FIG.

A first embodiment of the machine comprises an envelope or casing with an opening 2 on one side. This envelope 1 houses two similar door manipulation systems 3, each of which covers approximately 1/1/2 of the volume of said envelope.
2 and each has two parallel Archimedean helical screws 4. The axis of the Archimedean helical screw 4 is oriented in a direction that corresponds to the direction of passage through said opening 2. These Archimedean helical screws 4 are interconnected at one end thereof to a first pivoting bar 5 and at the other end to a second pivoting bar 6 . This second pivot bar 6 is fixed to one pivot shaft 7 mounted in the envelope 1 closer to the opening 2. On the other hand, the first pivot turning rod 5 is fixed to a movable pivot shaft 8 that traverses the side of the envelope 1 (the removable cover 9) located on the opposite side of the opening 2. One first motor 10 mounted outside the cover 9 drives the movable pivot shaft 8 .

The two rods 5 and 6 pivot, and one of the pivots
/2 At every revolution, one of the two door manipulation systems 3 passes in front of the opening 2. In this position, one square-section end 11 of the Archimedean helical screw 4 meshes in the member 12 against the end of the shaft 13 which pivots within the cover 9 in response to the movement of the shaft of the Archimedean helical screw 4 . A second motor 14 fixed on the outside of the cover 9 drives the two shafts 13 with identical movement by means of a transmission with a universal joint or gimbal joint 43 .

A panel 15 is attached to the Archimedean helical screw 4 of each door manipulation system 3. one rear flange 16 carrying a mating nut for the Archimedean helical screw 4; one cylindrical section 17 extending from said rear flange 16 in the direction of the opening 2; and one substantially enclosed by said cylindrical section 17. and a planar sealing plate 18 can be seen in FIG. A cylindrical area 17 and a sealing plate 18 delimit a door receiving cavity 19 to the front.

In the state of the machine shown in the figure, one panel 15 has been moved to the end of the Archimedean helical screw 4, and the Archimedean helical screw 4 supports said one panel 15 in such a way as to close the opening 2. do. On the other hand, the other panel 15 covers the outer enclosure 1 near the first pivot bar 5.
is withdrawn inside. This other panel 15 is
It holds one door 20 located within the cavity 19, which door 20 itself holds one component, such as a measuring device 21.

Several systems can be used to secure the door 20 onto the panel 15. It is possible to consider using one small air jack 44 with two states, articulated on the inner surface of the sealing plate 18. This movement of the rod 45 by the jack 44 operates the rotation of a shaft 46, which drives a disc 47 in front of the outer surface of the sealing plate 18. Means 48 fixed to the outer peripheral portion of the disk 47
A rod 49 articulated with 7 is moved, and this rod 49
slides in a bearing 50 on the sealing plate 18. The ends of the rods 49 enter into recesses (not shown) in the door 20 and thus press and secure the door 20 against the sealing plate 18. This system, also shown in FIG.
1, only one of which is shown in FIG. 1 to avoid overcomplicating the diagram.

[0015] In this design, the door manipulation system 3 is subjected to a circular movement, which requires that the width of the envelope 1 be of a constant dimension. In certain applications, dimensional constraints may require the envelope to be even narrower, as shown at 1' in FIG.

The above description can generally be transferred to the embodiment of FIG. 2, except that the door manipulation system 3 is operated by a shuttle system. In this case, the mechanism is constituted by two sliding rods 5' and 6' replacing the pivoting rods 5 and 6. The second sliding rod 6' is connected to the outer enclosure 1'.
It is moved over a support 7' fixed above. On the other hand, the first sliding rod 5' is provided with one rack, on which one pinion 51 meshes at the end of the movable pivot shaft 8. A support system (not shown) fixed to the envelope 1' keeps the first sliding rod 5' pressed against the pinion 51.

[0017] This construction requires the position of the opening 2 to be centered in the envelope 1, while one recess is provided on each side thereof for accommodating the door manipulation system when it is not in use. ing.

Reference is now made to FIG. One first gasket 22 is arranged around the opening 2 in the front face 23 of the envelope 1 and closes the examination entrance door 2 to the radiation area 26.
5 is pressed against the surrounding chamber wall 24. 1
Two second gaskets 27 are arranged outside the cylindrical area 17 and are pressed against the edge 28 of the opening 2 when the panel 15 is advanced. one third flat gasket 2 arranged on the outer side of the sealing plate 18 and surrounded by the front part of the cylindrical area 17;
9 is pressed against the door 25 to be replaced. On the other hand, one fourth gasket 30
is sandwiched between the front surface of the chamber and the chamber wall 24. Four gaskets 22, 27, 29, 30 delimit a closed annular volume 52 with the door 25, the compartment wall 24, the panel 15 and the envelope 1.

One liquid circuit is injected into said annular volume 52. Figure 3 shows one perforated pipe 3 passing through the outer envelope 1.
1, and this perforated pipe 31 is connected to one injection pump 32.
and one liquid tank 5 at the other end.
Terminates at 3. At a diametrically opposite position of the annular volume 52, a similar liquid circuit is formed by a pipe, a suction pump and a liquid tank. This assembly makes it possible to cause circulation of decontamination fluid within the annular volume 52 by means of two pumps. One of the nuts 33 can be seen in the diagram,
The nut is provided on the rear flange 16 for mating onto the Archimedean helical screw 4. Finally, the small room wall 2
4 is provided with a plurality of pins 34 whose shape matches the shape of the slots 35 in the envelope 1 in order to enable precise centering of the opening 2 around the door 25. is complementary.

To replace the door, first, insert the pin 34 into the slot 35 accurately, and then insert the pin 34 into the compartment wall 2.
It consists of placing an envelope 1 on top of 4. Gaskets 22 and 29 are pressed against the compartment wall 24 and door 25. If the chamber wall 24 is a ceiling, this pressure is obtained by the weight of the machine itself. If not, then
The envelope 1 can be flanged to the chamber wall 24 or pressed by any mechanical means.

Subsequently, the door 25 is fixed to the panel 15 using an air jack 44. The Archimedean helical screw 4 is then moved in order to pull up the panel 15 and remove the door 25. Contaminated contents of the irradiated area 26 may be transferred into the envelope 1. However, gaskets 22 and 29 prevent the leakage of contaminated contents to the outside and to the front of sealing plate 18. Without displacing the envelope 1 from the chamber wall 24, the shuttle mechanism rotates by half a turn to place the replacement door 20 in front of the opening 2. Thereafter, the panel 15 is moved forward until the door 20 is positioned over the radiation area 26, and the door 20 is subsequently removed from the panel 15. However, a sealed annular volume 52 has been re-formed, and this annular volume is decontaminated by injecting a cleaning liquid into this volume;
The used cleaning liquid is then sucked out.

[0022] The envelope 1 can then be removed. The panel 15 remains in the state shown in the figure in order to completely isolate the contaminated contents of the envelope 1 from the outside by means of the gasket 27 which hermetically closes the opening 2.

After placing the machine on a container having a shape similar to the shape of the chamber wall 24, a contaminated door such as 25 is taken out of the enclosure 1. A contaminated door is placed over the opening of the container in the manner described above, after which decontamination takes place and the machine is removed.

[0024] In many cases, the total weight of the door and the optional measuring device 21 is the same as that of the chamber wall 2.
4. Appropriately sized to provide proper support on top of 4. However, if this is not the case, it is possible to use a system such as that of FIG. One bracket 39 rests on two centering pins 34 located diametrically opposite each other. 1 pressure pad 4
0 is placed on the door 20 below the bracket 39.

A threaded shaft 41 with a handle wheel 42 attached to its end is arranged such that the other end of the shaft contacts a pressure pad 40 to exert a force or load on the pad. It engages the top of the bracket 39 to hold the door 20 in place. A thread is cut at the tip of the centering pin 34. These centering pins 34 extend through holes in the bracket 39 and nuts are screwed onto the threads of the pins to hold the bracket 39 in place.

FIG. 5 shows how the machine of the invention is used. A bioprotective wall 55 surrounds the chamber wall 24 . Two rails 56 are fixed to the inner side of the bioprotective wall 55 and one carriage 57 runs on these rails. Two slides 58 on the carriage 57 allow the lower carriage 59 to run at right angles to said rail 56.

The envelope 1 is arranged at the end of the rod of the jack 60, the cylinder of which is fixed to the lower carriage 59. Extension of the rod of the jack 60 allows the machine of the invention to be engaged against the chamber wall 24. A camera 61 monitors the volume between the two walls 24 and 55 and indicates whether the machine is in the desired position. At its opposite end, the rail 56 reaches a compartment in which the treatment of the machine takes place. In particular, within this compartment, a container containing a contaminated door or a new door is placed in place.

FIG. 5 shows the device mounted on the rail 56 in the case where the cell wall is the ceiling, as in FIGS. 1-4. This device can be used with rails 56 and compartment walls 24 having any orientation.

In the same manner as the air jack 44, the motors 10 and 14 are controlled by electrical cables or the like that extend outside the bioprotective barrier. These electrical cables or the like are not shown in order not to overcomplicate the diagram.

[Brief explanation of the drawing]

1 is a general view of one embodiment of a door changing machine according to the invention; FIG.

FIG. 2 is a general view of another embodiment of a door changing machine according to the invention;

FIG. 3 is an explanatory diagram showing a sealing device according to the present invention.

FIG. 4 is a structural diagram of an inspection entrance door according to the present invention.

FIG. 5 is an explanatory diagram showing the environment of the present invention.

FIG. 6 is a front view of the door support according to the invention.

[Explanation of symbols]

1 Envelope 2 Opening 3 Door manipulation system 7, 8, 10
Shuttle mechanism 15 Door support 20, 25 Inspection entrance door 22 First gasket 24 Chamber wall 26 Contaminated area 27 Second gasket 29 Third gasket 31, 32, 53 Decontamination device 35 Slot 52 Closed annular volume 55 Living body protective wall

Claims (6)

[Claims] 1. A machine for replacing inspection entrance doors to contaminated areas, comprising an envelope having an opening and housing two door manipulation systems, each of said door manipulation systems but,
one door support, and means for securing the door to the support, the envelope being such that the door support is suspended below and each of the door supports also accommodates a shuttle mechanism configured to be able to be positioned alternately within said opening, said machine connecting said enclosure with a wall delimiting the area of contamination. a first gasket disposed around the aperture forming a seal therebetween; a second gasket disposed within the opening forming a seal between the door and the door support; and a second gasket disposed on the door support forming a seal between the door and the door support. a third gasket and a device for decontaminating a sealed volume delimited by the three gaskets. 2. Machine according to claim 1, characterized in that the third gasket is one flat gasket located at the bottom of the cavity of the door support. 3. Machine according to claim 1, characterized in that means are provided in the envelope for centering the opening around the door. 4. The shuttle mechanism having a rotating structure for moving each of the door supports in front of the opening and motor means for sliding the door support within the opening. Machine according to claim 1, characterized in that: 5. The shuttle mechanism comprises a structure movable in an alternating manner for moving each of the door supports in front of the opening and sliding the door supports within the opening. 2. A machine according to claim 1, further comprising motor means for. 6. The biological protection wall and the wall delimiting the contaminated area, characterized in that the machine is used between the outer biological protection wall and the wall delimiting the contaminated area. Use of the machine according to claim 1 in a facility constituted by.