Device for blocking a passage

Abstract

A removable obturation device is provided for transversely obstructing a passage delimited by a cylindrical side wall wherein it includes: a) a support and blocking element having a central block supporting a plurality of arms disposed perpendicularly in a radial position with respect to the longitudinal axis of the block and of the side wall, each arm having an extensible rod including a pad intended to be blocked against one the side wall, and b) at least one complementary obturation element extending in a radial transverse plane perpendicular to the longitudinal axis, at least partly in or opposite the space between the arms so as to prevent an individual from falling through the passage. The obstruction element is preferably removably fastened to the support and blocking element.

Claims

1. A removable obturation device for transversely obstructing a passage delimited by a cylindrical side wall having a longitudinal axis, comprising: a) a support and blocking element comprising a central block having a longitudinal axis configured to be positioned in the longitudinal axis of said side wall of said passage, the central block supporting a plurality of different arms disposed perpendicularly in a radial position with respect to said longitudinal axis of said central block, the different arms being disposed symmetrically with respect to said longitudinal axis of said central block; each arm comprising an extensible rod comprising a pad at a free end thereof, the pad fastened in a reversible manner to the free end of said extensible rod, configured to be blocked in abutment against one said side wall by extension of said extensible rod, and b) at least one complementary hoop-shaped obturation element extending in a transverse plane perpendicular to said longitudinal axis of said passage, at least partly in or opposite a space between said arms so as to prevent an individual from falling through said passage, said obturation element being removably fastened to said support and blocking element; c) a removable actuation element configured to cooperate with said central block to actuate in extension or retraction said extensible rods of said arms simultaneously, said actuation element comprising first reversible fastening means on said support and blocking element, at said central block, said first reversible fastening means configured to reversibly fasten said actuation element on said obturation element.

2. The device according to claim 1, wherein said support and blocking element comprises four said arms disposed in a cross at 90 around the central block.

3. The device according to claim 1, wherein said actuation element comprises a handwheel-shaped gripping element around a geared motor to which fastened.

4. The device according to claim 1, wherein said actuation element comprises a geared motor configured to actuate in rotation along a longitudinal axis of a motor shaft, and said support and blocking element comprises: a1) said arms each comprising one drive shaft disposed in one longitudinal direction in a perpendicular radial plane with respect to said longitudinal axis of said central block, each said drive shaft being configured to be driven in rotation along a radial longitudinal axis thereof and configured to cooperate with one said extensible rod in coaxial translation by helical link such that rotation in either direction of said drive shaft causes translation of said extensible rod in extension or respectively in retraction in one radial direction, and a2) one said central block comprising an input shaft disposed along the longitudinal axis of said central block and configured to be actuated in rotation with respect to a longitudinal axis of the input shaft when cooperates with said motor shaft of said actuation element, and an angle transmission device comprising bevel gears configured to cooperate with each other at ends of said input shaft and said drive shafts so that rotation along the longitudinal axis of said input shaft simultaneously causes rotations on of said drive shafts along respective axes in radial directions.

5. The device according to claim 4, wherein said helical link is a screw-nut helical link, said drive shaft comprising an external helical threading forming a screw cooperating with a tubular rod at least one end portion of which forms a nut engaged on the threading of the threaded screw formed by said drive shaft, said nut being prevented from following said rotation of said drive shaft and said tubular rod being guided in said translation by a guide pin of said nut due to said guide pin cooperates with a rectilinear inner slot of a guide and protection cylinder inside which said drive shaft and one end portion at least of said tubular rod extend coaxially, free end of the rod comprising said pad always remaining outside said guide and protection cylinder.

6. The device according to claim 1, wherein said obturation element comprises a single obturation element extending above said arms, configured to be removably fastened to said support and blocking element at said central block.

7. The device according to claim 6, wherein said obturation element comprises a hoop linked to a central hub by spokes, said central hub of said hoop being configured to be removably fastened to said support and blocking element around said central block so that said spokes of the hoop extend between said arms, along bisectors of angles between said arms.

8. The device according to claim 1, wherein said actuation element comprises said first reversible fastening means on said obturation element, at a central hub of said hoop-shaped obturation element, and comprising second reversible fastening means on said support and blocking element, at said central block.

9. The device according to claim 8, wherein said actuation element comprises a handwheel-shaped gripping element around a geared motor to which fastened, said handwheel comprising first reversible locking means allowing blocking of the reversible fastening of said actuation element on said obturation element, by a movement of relative axial rotation about longitudinal axis of a magnet ring rotating with respect to said handwheel and on underside of said handwheel, at least one magnet of said ring being configured to cooperate with respectively at least a first metal elastic locking pin in a hole of said obturation element, said first metal locking pin being configured to leave said hole attracted against said magnet, by a first spring, when positioning of said actuation element with respect to said obturation element on and the rotation of said ring places said magnet opposite the first elastic locking pin of said obturation element, opposite a first elastic locking pin in a hole at a central hub of said hoop-shaped obturation element.

10. The device according to claim 9, wherein said obturation element comprises second reversible locking means allowing a blocking of the reversible fastening on said support and blocking element of assembly of said actuation element fastened to said obturation element, by movements of relative axial rotation and translation with respect to said support and blocking element of the assembly of said actuation element fastened to said obturation element, along and respectively about a longitudinal axis thereof.

11. The device according to claim 10, wherein said hoop-shaped obturation element and said second reversible locking means comprise: at a central hub of said obturation element, at least a second locking pin and a second spring in a cylindrical recess within said central block, and on outer wall of said central block, at least one locking slot comprising a first vertical portion along longitudinal direction of said block, a second circular-arc portion on periphery of said block and a third vertical portion, said second circular-arc portion forming junction of lower ends of said first and third vertical portions, said first vertical portion being open at an upper end and said third vertical portion being closed at the upper end, so that said second reversible locking means are configured to be actuated in locking by: a first downward vertical translational movement of the assembly of said actuation element fastened to said obturation element with respect to said central block and coaxially therewith along a longitudinal axis thereof, said second locking pin thus being configured to be guided in translation in said first vertical slot portion up to a lower end by compressing said second spring in doing so, a second rotational movement of the assembly of said actuation element fastened to said obturation element with respect to said central block, said second locking pin thus being configured to be guided in rotation in said second circular slot portion up to the lower end of said third vertical slot portion, keeping said second spring compressed, and a third upward vertical translational movement of the assembly of said actuation element fastened to said obturation element with respect to said central block and coaxially therewith along a longitudinal axis thereof, said second locking pin thus being configured to be guided in translation in said third vertical slot portion up to the upper end due to extension of said second spring.

12. A method of setting up the obturation device according to claim 1, comprising: a) positioning the obturation device in said passage with the extensible rods of said arms in the retracted position, said arms being disposed in a perpendicular radial plane with respect to said longitudinal axis of said central block disposed coaxially with the axis of said passage, and b) actuating, by means of one said actuation element, said arms to block said pads in abutment against the cylindrical wall of said passage by extension of the said extensible rods, said actuation element cooperating with said central block to actuate in extension said extensible rods of said arms simultaneously.

13. The method according to claim 12, comprising preliminary steps of: a1) fastening on said obturation element one said actuation element comprising a handwheel-shaped gripping element, then a2) fastening said actuation element assembled with said obturation element on said central block of said support and blocking element.

14. The method according to claim 12, further comprising: a) positioning said obturation device in said passage with the extensible rod of said arms in the retracted position, using a handwheel-shaped gripping element fastened around a geared motor of said removable actuation element, and b) actuating said arms to block said pads in abutment against the cylindrical wall of said passage by extension of said extensible rods using said geared motor of said actuation element, and c) removing said removable actuation element to let in the passage only said support and blocking element and said obturation element.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) Other characteristics and advantages of the present invention will emerge more clearly upon reading the following description, given in an illustrative and non-limiting manner, with reference to the appended drawings in which:

(2) FIG. 1 represents a perspective view of an obturation device according to the invention with one said support and blocking element 2 supporting an obturation element 6 and an actuation element 10.

(3) FIG. 2A represents a first variant of an obturation device according to the invention placed in a manhole 20 with a cylindrical vertical underground wall having a circular section 20a, with one said support and blocking element 2 supporting an obturation element 6.

(4) FIG. 2B represents a second variant of an obturation device according to the invention placed in a manhole 20 with a vertical cylindrical underground wall having a square section 20b, with one said support and blocking element 2 supporting an obturation element 6 and an actuation element 10.

(5) FIG. 3A represents a perspective view of said support and blocking element 2 of an obturation device according to the invention.

(6) FIG. 3B represents a top view of one said support and blocking element 2 of an obturation device according to the invention.

(7) FIG. 3C represents an axial vertical sectional view along XX of one said support and blocking element 2 of an obturation device according to the invention with the retracted rod 3b.

(8) FIG. 3D represents an axial vertical sectional view along XX of one said support and blocking element 2 of an obturation device according to the invention with the rod 3b in extension.

(9) FIG. 4 represents a perspective view of the cylindrical walls 2a1 and 2a2 delimiting an empty space 2a3 of a central block 2a devoid of the input shaft 2b of one said support and blocking element 2.

(10) FIG. 4A represents an axial vertical sectional view along XX showing the detail of the helical link of the drive shaft 3a and of the extensible rod 3b of an arm 3 of one said support and blocking element 2 of an obturation device according to the invention.

(11) FIG. 4B represents an axial vertical sectional view along XX showing the detail of the reversible link of the end of the extensible rod 3a with a pad 4 of one said support and blocking element 2 of an obturation device according to the invention.

(12) FIG. 5A represents a perspective view of an actuation element 10 with geared motor 11 and handwheel 12 with a magnet ring 9 on the underside.

(13) FIG. 5B represents an axial vertical sectional view along ZZ of an actuation element 10 with geared motor 11 and handwheel 12 with a magnet ring 9 on the underside.

(14) FIG. 6A represents a perspective view of a hoop-type obturation element 6.

(15) FIG. 6B represents an axial vertical sectional view along ZZ of a hoop-type obturation element 6.

(16) FIG. 7A represents a perspective view of the fastening of an actuation element 10 of FIGS. 5A and 5B on a hoop-type obturation element 6 of FIGS. 6A and 6B.

(17) FIG. 7B represents an axial vertical sectional view along ZZ of the fastening of an actuation element 10 of FIGS. 5A and 5B on a hoop-type obturation element 6 of FIGS. 6A and 6B.

(18) FIG. 8A represents an axial vertical sectional view along ZZ of the detail of the operating mode of the fastening of an actuation element 10 on a hoop-type obturation element 6 of FIGS. 7A and 7B, showing the cooperation of the magnet ring 9 and of the first locking pin 8 without locking.

(19) FIG. 8B represents an axial vertical sectional view along ZZ of the detail of the operating mode of the fastening of an actuation element 10 on a hoop-type obturation element 6 of FIGS. 7A and 7B, showing the cooperation of the magnet ring 9 and of the first locking pin 8 in the locking position before locking.

(20) FIG. 9A represents a horizontal sectional view along AA of FIG. 8A.

(21) FIG. 9B represents a horizontal sectional view along AA of FIG. 8B.

(22) FIG. 10 comprises FIGS. 10A-10C which represent vertical sectional views along ZZ showing the cooperation of a locking pin 13 of a central hub 6c-6d of a hoop-type obturation element 6 during its locking on a central block 2a of one said support and blocking element 2 by movements of vertical translation and rotation along ZZ of said assembly 10, 6 with respect to said central block 2a according to FIGS. 10A-10C respectively.

(23) FIG. 11 comprises FIGS. 11A-11C which represent perspective views showing the cooperation of a locking pin 13 of a central hub 6c-6d of a hoop-type obturation element 6 during its locking on a central block 2a of one said support and blocking element 2 by movements of vertical translation and rotation along ZZ of said assembly 10, 6 with respect to said central block 2a according to FIGS. 10A-10C respectively.

DETAILED DESCRIPTION OF VARIOUS EMBODIMENTS

(24) FIGS. 1 to 11 represent one embodiment of a manhole obturation device according to the invention 1 comprising 3 elements which can be fastened to each other by reversible locking means, namely: a support and blocking element 2 comprising a central block 2a enclosing an angle transmission bevel gear device 5 cooperating with four arms 3 disposed in a cross with their longitudinal axes in directions XX and YY perpendicularly and radially with respect to the axis ZZ of said central block 2a to which they are linked, and a complementary hoop-type obturation element 6, and an actuation element 10 comprising (a) an electric geared motor 11 able to actuate a motor shaft 11a along the axis ZZ cooperating with the angle transmission device 5 and (b) a handwheel-shaped gripping element 12.

(25) In practice, the fastening of said actuation element 10 is carried out on said obturation element 6, which facilitates the fastening of said obturation element 6 on said central block 2a of said support and blocking element 2 with said handwheel-shaped gripping element 12. Then, said handwheel-shaped gripping element 12 facilitates the set-up of said obturation device according to the invention 1 with its 3 thus assembled elements 2, 3 and 10.

(26) FIGS. 1 and 2B show the obturation device according to the invention 1 with its 3 thus assembled elements 2, 3 and 10. FIGS. 2A and 2B show the obturation device according to the invention 1 in the blocking position with the blocking pads 4 in abutment against the cylindrical wall 20a by extension of the extensible rods 3b disposed in a radial plane XX, YY perpendicular to the longitudinal axis of the central block 2a itself disposed coaxially with the axis ZZ of the cylindrical walls 20a and 20b. In FIG. 2A, said actuation element 10 comprising a gripping element 12 and a geared motor 11 has been removed in order to be used for the set-up of another obturation device in another hole 20.

(27) FIGS. 3A-3D show the structure and the operation of the arms 3 mounted on the central block 2a of the support and blocking element 2.

(28) Each arm 3 comprises a drive shaft 3a disposed in one said longitudinal direction in a perpendicular radial plane XX, YY with respect to said longitudinal axis ZZ of said central block 2a. Each drive shaft 3a passes at a first end through an orifice 2-1 of the cylindrical wall 2a2 of the block 2a shown in FIG. 4 and ends at said first end by a bevel gear 5a opening out inside an empty space 2a3 delimited by the wall 2a2 of said central block 2a.

(29) As shown in FIG. 3A, said central block 2a comprises an input shaft 2b disposed along the longitudinal axis ZZ of said central block 2a and ends at its lower end by a bevel gear 5b inside the empty space 2a3 delimited by the wall 2a2 of said central block 2a. The bevel gear 5b at the end of the input shaft 2b is able to cooperate with the 4 gears 5a at the ends due to the drive shafts to form an angle transmission device 5. The input shaft 2b comprises an axial recess 2d open in the upper portion of the central block 2a able to receive and cooperate with the motor axis 11a of the geared motor 11. Thus, the input shaft 2b can be actuated in rotation on itself with respect to its longitudinal axis ZZ when it cooperates with said motor shaft 11a of said actuation element 10 and when the geared motor is electrically actuated. The rotational actuation of said input shaft 2b allows actuating in rotation the meshed bevel pinions 5a and 5b of the angle transmission device 5 so that the rotation on itself along its longitudinal axis ZZ of said input shaft 2b simultaneously drives the rotations on themselves of said drive shafts 3a along their axes in their said radial directions XX, YY.

(30) As shown in FIGS. 3B-3D and 4A-4B, each arm 3 comprises a drive shaft 3a comprising an external peripheral helical threading 3a1 forming a screw cooperating with a nut 3b1 engaged on the threading 3a1, said nut 3b1 being fastened to the end of a tubular extensible rod 3b able to coaxially cover said drive shaft 3a when the tubular rod 3b is in the retracted position with the nut 3b1 furthest from the central block 2a as shown in FIG. 3C and able to extend beyond the drive shaft 3a when the tubular rod 3b is in the extended position shown in FIG. 3D with the nut 3b1 furthest from the central block 2a.

(31) A guide pin 3b2 on the periphery of the nut 3b1 cooperates with a rectilinear inner slot 3cl of a guide and protection cylinder 3c coaxially covering said drive shaft 3a and said tubular rod 3b in the retracted position. Thus, said drive shaft 3a is able to cooperate with said extensible tubular rod 3b in coaxial translation by helical link due to the fact that when said drive shaft 3a is driven in rotation on itself along its radial longitudinal axis XX, YY, said rotation on itself in either direction of said drive shaft 3a causes the translation of said tubular rod 3b in extension or respectively in retraction in one said radial direction XX, YY due to the fact that the nut 3b1 and therefore said tubular rod 3b which is fastened thereto are prevented from rotating on themselves by the blocking and the guiding of the pin 3b2 in the slot 3c2 thus forcing said coaxial translation of said rod 3b. The tubular rod 3b slides in translation through a terminal ring 3c2 closing the annular space between the guide and protection cylinder 3c and the tubular rod 3b at the end of the guide and protection cylinder 3c.

(32) In FIG. 3B, on the upper and right arms 3, the guide and protection cylinder 3c has not been represented to mount the drive shafts 3a which are otherwise concealed by said cylinders 3c. Said guide and blocking cylinder 3c also acts as a protection for the rod 3b and drive shaft 3a assembly in a helical link.

(33) The free end of the tubular rod 3b furthest from the central block 2a comprises a pad 4 always remaining outside said guide and protection cylinder 3c when the rod 3b is in the maximum retracted position.

(34) FIG. 4B represents one embodiment of a reversible fastening of the pad 4 at the end of the rod 3b using a ball ring system by which a sliding ring on a cylindrical bead 4a of the pad 4 covers and holds a ball 3dl in a groove of a terminal part 3d at the end of the rod 3b. It suffices to pull the sliding ring 4b on the bead 4a to elastically release the ball 3dl out of the groove of the terminal part 3d at the end of the cylindrical rod 3b in order to be able to separate the pad 4 from the rod 3b. This reversible locking is quick and ergonomic. Thus, it is possible to change the pad 4 so that the latter has a shape adapted to the surface of the cylindrical side wall 20a, 20b of the passage 20 against which it must be applied in abutment.

(35) The pad 4 comprises an end part 4c fastened to the bead 4a which ensures the link to the end of the arm 3, preferably an end part 4c made of rigid elastomer material. The end part 4c has a longitudinal shape in the direction ZZ of the axis of the passage or hole 20. The end part 4c comprises a contact surface 4d with the cylindrical wall 20a, 20b of the passage 20 which has a cross-sectional contour in the plane XX, YY which follows the cross-sectional contour of said cylindrical wall 20a, 20b in the plane XX, YY.

(36) FIGS. 5A and 5B represent an actuation element 10 with geared motor 11 and a handwheel-shaped gripping element 12 and a magnet ring 9 on the underside intended for the reversible locking of said actuation element on a hoop-type obturation element 6 represented in FIG. 6A-6B.

(37) The geared motor 11 is able to actuate in rotation place along the axis ZZ of a passage 20 with a cylindrical wall 2a, 20b. A gripping element 12 comprises a circular handwheel 12a and a first coaxial central hub 12c linked to each other by first linking elements by forming first spokes 12b disposed in a cross (at 90). The tubular wall of the first central hub 12c is surmounted by said geared motor which is fastened thereto by studs 11b and delimits a first central cylindrical recess 12cl traversed by said motor shaft 11a disposed coaxially along the axis ZZ. On the underside of the tubular wall of the first central hub 12c is disposed coaxially a ring 9 which is fastened thereto by a circular fastener 9-1 coaxial along ZZ so that the ring 9 is able to be driven manually in relative rotation with respect to said first central hub 12c to achieve the reversible locking of said actuation element on a hoop-type obturation element 6 represented in FIG. 6A-6B while maintaining said ring secured to the underside of the tubular wall of said first central hub 12c.

(38) The ring 9 comprises two magnets 9a in two diametrically opposed first empty housings 9b.

(39) FIGS. 6A-6B represent a hoop-type obturation element 6 comprising: a second central hub 6c of axis ZZ and a peripheral circular rim 6a of axis ZZ when the element is in place coaxially on the device of the invention 1 in the passage 20, and 4 second spokes 6b disposed in a cross (at 90) in a radial plane XX, YY ensuring the link with respect to a second central hub 6c of axis ZZ and a wheel rim 6a.

(40) The hoop 6 is intended to be positioned above the support and blocking element 2 with the second spokes 6b disposed from the 4 arms 3 in the directions of the bisectors of the empty spaces 3-1 between two adjacent arms 3. The second spokes 6b have a length such that the rim 6a arrives at the level of the end 3c2 of the protection cylinder 3c. In practice, the hoop 6 and the protection cylinders 3c of the arms 3 are dimensioned such that the arms 3 being in maximum extension with the pads 4 in abutment on the lateral surface 20a, 20b, the rim 6a arrives approximately to the half the length of said arms 3, that is to say the length of the protection cylinders 3c represents approximately half the length of said bars 3 in maximum extension.

(41) The second central hub 6c is of tubular shape delimiting a coaxial cylindrical internal recess 6e of axis ZZ. The second central hub 6c is surmounted by a coaxial upper portion 6d of cylindrical tubular shape forming a shoulder 6cl at the junction between the second central hub 6c and its upper portion 6d. The upper portion 6d delimits an internal recess 6el of smaller diameter than the recess 6e and communicating therewith.

(42) The shoulder 6cl is able to support the circular fastener 9-1 and the ring 9 on the underside of the tubular wall of the first central hub 12c when said actuation element 10 comprising the geared motor 11 and the handwheel 12 are assembled on the hoop 6 by coaxially threading the ring 9 and the tubular wall of the first central hub 12c on the upper portion 6d surmounting the second central hub 6b as shown in FIGS. 7A-7B.

(43) The tubular wall of the upper portion 6d surmounting the second central hub 6c comprises at its lower end close to the shoulder 6c1, two diametrically opposed second hollow housings 8b enclosing respectively two first locking pins 8.

(44) A second coaxial spring 7 which serves for the reversible locking of the hoop 6 on the support and blocking element 2 is disposed within the recess 6e delimited by the tubular wall of the first central hub 12c. The tubular wall of the first central hub 12c has four second locking pins protruding on its inner face protruding towards the central recess 6e. The second spring 7 and the second locking pins are able to cooperate with outer slots 2c on the periphery of the walls of the central block 2a of the support and blocking element 2 in order to achieve a reversible locking of the hoop 6 on the central block 2a.

(45) In FIGS. 8A-9A, the ring 9 is in a position of relative with respect to the second central hub 6c and its upper portion 6d such that the two first locking pins 8 are held in the hollow housings 8b by compressing first springs 8a due to the fact that the first hollow housings 9b are not positioned opposite the second hollow housings 8b.

(46) In FIGS. 8B-9B, the ring 9 is in a position of relative rotation with respect to the second central hub 6c and its upper portion 6d such that the two first hollow housings 9b are positioned opposite the second hollow housings 8b. Thus, the first two metal locking pins 8 are ready to be attracted by the magnets 9a and leave the second hollow housings 8b by extension of the first springs 8a due to the fact that the first hollow housings 9b are not positioned opposite the second hollow housings 8b. A new rotation of the ring 9 will cause the entry of the first two metal locking pins 8 into the second hollow housings 8b and the compression of the first springs 8a.

(47) FIGS. 10A-11A, 10B-11B, 10C-11C represent the operation of the second reversible locking means allowing the reversible fastening of the hoop 6 on the central block 2a of said support and blocking element 2, by movements of relative axial rotation and translation of the assembly of said actuation element 10 fastened to said obturation element 6 with respect to said support and fastening element 2, along and respectively about said longitudinal axis ZZ.

(48) FIG. 4 represents the outer wall of said central block 2a comprising four slots 2c each comprising a first vertical portion 2cl along the longitudinal direction (ZZ) of said block, a second circular-arc portion 2c2 on the periphery of said cylindrical block 2a corresponding for example to a 45 rotation, and a third vertical portion 2c3, said second circular-arc portion 2c2 forming the junction of the lower ends of said first and third vertical portions 2c1, 2c3, said first vertical portion 2cl being open at its upper end and said third vertical portion 2c3 being closed at its upper end.

(49) FIG. 10A shows a first downward vertical translational movement of the assembly of said actuation element 10 fastened to said obturation element 6 with respect to said central block 2a and coaxially therewith along its longitudinal axis ZZ, by engaging the motor shaft 11a in an upper axial orifice 2d of the input shaft 2b of said central block 2a, before the second central hub 6c of the hoop 6 abuts on the shoulder 2e of the central block 2a, the second spring 7 being in extension.

(50) FIG. 11A shows the sequence of the first downward vertical translational movement of the assembly of said actuation element 10 fastened to said obturation element 6 with respect to said central block 2a and coaxially therewith along its longitudinal axis ZZ, said second blocking pin 13 of the hoop 6 being engaged and guided in translation in said first vertical slot portion 2c1. This first movement continues until the second central hub 6c of the hoop 6 abuts on the shoulder 2e of the central block 2a and the pin 13 arrives at the lower end of said first vertical slot portion 2cl by compressing said second spring 7 in doing so as shown in FIG. 10B. This first downward vertical translational movement is facilitated by the gripping and the axial positioning of the assembly of said actuation element 10 fastened to said obturation element 6 with respect to said central block 2a, using the handwheel 12.

(51) At this stage, as shown in FIG. 11B, by turning the handwheel 12, a second rotational movement of the assembly of said actuation element 10 fastened to said obturation element 6 with respect to said central block 2a is carried out, said second blocking pin 13 thus being guided in rotation in said second circular slot portion 2c2 up to the lower end of said third vertical slot portion 2c3, while keeping said second spring 7 compressed.

(52) FIGS. 10C and 11C show a third upward vertical translational movement of the assembly of said actuation element 10 fastened to said obturation element 6 with respect to said central block 2a and coaxially therewith along its longitudinal axis ZZ, said second blocking pin 13 thus being guided in translation in said third vertical slot portion 2c3 up to its upper end due to the extension of said second spring 7.

(53) The obturation device according to the invention is an articulated system of 4 arms that allows blocking the passage of a manhole. The arm extension system has been described as being preferably an electromechanical system operating via a screw-nut system to make a helical link causing the deployment of the rod accompanied by a gear torque multiplier to provide the required force with bevel gears to redirect the axes of rotation. The input shaft 2b is rotated via the motor axis 11a and the bevel gear system 5 allows the redirection of the main rotation on the 4 secondary shafts 3a which drive the helical link (screw-nut). Thus, also thanks to the blocking of the rotation of the output rod 3b via a slot 3cl in the guide 3c, the system is deployed. It is under stress during the contact of the pads 4 with the walls of the manhole 20.

(54) However, they can be substituted with hydraulic or pneumatic jacks, thus providing a slide link or sliding pivot link rather than a helical link, said jacks being coupled on a hydraulic or pneumatic fluid supply. In this case, manual pre-adjustment is required to reduce the used volume of fluid.

(55) The obturation device according to the invention is adaptable to all manhole geometries and dimensions thanks to a stress made on the walls of the hole by activation of the arm extension system.

(56) The obturation device according to the invention is mainly used for prevention in case of flooding (the system can be sealed), prevention during work, or obturation of possible exits in the event of an attack. In these multiple cases, the obturation device according to the invention allows preventing a person from falling through the manhole or prohibiting the voluntary passage of an individual.

(57) A method for setting up an obturation device according to the invention 1 in order to transversely obstruct a passage 20 delimited by a cylindrical side wall 20a, 20b, comprises the steps of: 1) fastening on said obturation element 6, one said actuation element 10 comprising a handwheel-shaped gripping element 12, then 2) fastening on said central block 2a of said support and blocking element 2, the assembly of said actuation element 10 assembled with said obturation element 6, and 3) positioning, using the handwheel-shaped gripping element 12, the device according to the invention in said passage 20 with the extensible rods 3b of said arms in the retracted position, said arms being disposed in a perpendicular radial plane XX, YY with respect to said longitudinal axis ZZ of said central block 2a itself disposed coaxially with the axis of said passage 20, and 4) actuating the geared motor 11 to actuate in extension said four extensible rods 3b simultaneously said arms 3 in extension to block said pads 4 in abutment against the cylindrical wall 20a, 20ab of said passage as shown in FIG. 2A-2B, and 5) removing said removable actuation element 10 to let in the passage only the assembly of said support and blocking element 2 and said obturation element 6 as shown in FIG. 2A.

(58) The obturation hoop 6 is locked via a simple mechanical action made by the user on the handwheel 12. The locking pins 13 must therefore be aligned with the slots 2cl present on the central block 2a. Then, the assembly is depressed, and a 45 rotation is exerted in the slot 2c2. Finally, the handwheel 12 is loosened, which allows the assembly to move up thanks to the spring 7. The locking pins 12 will thus be blocked in the slot 2c3. The unlocking is simple: the actions listed in reverse order must be made.

(59) In step 5), the separation of the handwheel 12 is exerted by a simple 30 rotation of the magnet ring 9.