Pressure maintaining unit and inversion device

Abstract

To stabilize construction using a flexible cylindrical body.SOLUTION: A pressure holding unit (11) used in an inversion device that injects a pressurized fluid into a pressure vessel in which an insertion part (24) into which a flexible cylindrical body (L1) is inserted is formed, and inverts the flexible cylindrical body (L1) so that an inside becomes an outside includes: a guide member (5) that guides the flexible cylindrical body (L1); and a pressure holding member (8) that is provided on the guide member (5) and is deformed by the pressure of the pressurized fluid injected into the pressure vessel so as to come into close contact with the flexible cylindrical body (L1).SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a pressure-maintaining unit and an inversion device. [Background technology]

[0002] Patent Document 1 discloses an inverting device in which the tip of a flexible cylindrical body introduced through a slit formed at the rear end of a pressure vessel is fixed in a ring shape to a nozzle provided at the front end of the pressure vessel. The inverting device applies pressure to the pressure vessel with the tip of the flexible cylindrical body fixed to the nozzle, thereby inverting the flexible cylindrical body so that the inside becomes the outside and discharging it from the nozzle. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 5-38757 Summary of the Invention [Problem to be solved by the invention]

[0004] However, with the turning-over device disclosed in Patent Document 1, when a flexible cylindrical body is introduced through a slit formed at the rear end of a pressure vessel, there is a risk of compressed air leaking from the slit. Therefore, with the above turning-over device, there is a problem that the internal pressure required to turn the flexible cylindrical body inside the pressure vessel cannot be sufficiently secured, and the flexible cylindrical body may not be turned inside out. One aspect of the present invention aims to stabilize construction using a flexible cylindrical body. [Means for solving the problem]

[0005] In order to solve the above problems, one aspect of the present invention provides a pressure holding unit used in an inversion device that injects pressure fluid into a pressure vessel having a rear end where an insertion section into which a flexible cylindrical body is inserted is formed, and a front end where the tip of the flexible cylindrical body is fixed, and inverts the flexible cylindrical body so that the inside becomes the outside, and includes: a guide member that is provided in the insertion section and guides the flexible cylindrical body inserted into the insertion section to the front end; and an annular pressure holding member that is provided on the guide member and formed to extend in the insertion direction of the flexible cylindrical body, and that deforms due to the pressure of the pressure fluid that is pressed into the pressure vessel by the inversion device and adheres closely to the flexible cylindrical body.

[0006] In addition, in order to solve the above-mentioned problems, an inversion device according to one embodiment of the present invention comprises a pressure vessel having a rear end where an insertion section into which a flexible cylindrical body is inserted is formed, and a front end where the tip of the flexible cylindrical body is fixed; a press-fitting unit that pressurizes a pressurized fluid into the interior of the pressure vessel to invert the flexible cylindrical body so that the inside becomes the outside; a guide member that is provided in the insertion section and guides the flexible cylindrical body inserted into the insertion section to the front end; and an annular pressure-retaining member that is provided on the guide member and is formed to extend in the insertion direction of the flexible cylindrical body, and that deforms due to the pressure of the pressurized fluid that is pressed into the interior of the pressure vessel by the press-fitting unit to adhere to the flexible cylindrical body. [Effects of the Invention]

[0007] According to one aspect of the present invention, construction using a flexible cylindrical body can be stabilized. [Brief explanation of the drawings]

[0008] [Figure 1] 1 is a cross-sectional view showing the configuration of an inversion device according to a first embodiment of the present invention. [Figure 2] FIG. 2 is an enlarged view of a portion surrounded by a dotted line A1 shown in FIG. [Figure 3] FIG. 2 is a cross-sectional view taken along the line B1-B1 shown in FIG. [Figure 4] 2 is a perspective view showing the configuration of a pressure-retaining unit provided in the inverting device shown in FIG. 1. FIG. [Figure 5] 5 is a perspective view for explaining the length of the inner periphery of a pressure-retaining member included in the pressure-retaining unit shown in FIG. 4. FIG. [Figure 6] FIG. 10 is a perspective view showing the configuration of a pressure-retaining unit included in an inversion device according to a second embodiment of the present invention. [Figure 7] FIG. 10 is a perspective view showing the configuration of a pressure-retaining unit included in an inversion device according to a third embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0009] [Embodiment 1] <Configuration of Reversing Device 1> Fig. 1 is a cross-sectional view showing the configuration of an inversion device 1 according to a first embodiment of the present invention. Fig. 2 is an enlarged view of a portion surrounded by dotted line A1 shown in Fig. 1. Fig. 3 is a cross-sectional view taken along line B1-B1 shown in Fig. 1. In Figs. 1 and 2, the insertion direction in which a flexible cylindrical body L1 is inserted into an insertion portion 24 formed in a pressure vessel 2 is defined as the X-axis direction, the direction perpendicular to an installation surface S1 on which the inversion device 1 is installed is defined as the Z-axis direction, and the direction perpendicular to both the X-axis direction and the Z-axis direction is defined as the Y-axis direction. The X-axis direction, the Y-axis direction, and the Z-axis direction are perpendicular to each other.

[0010] As shown in FIG. 1, the inversion device 1 includes a pressure vessel 2, a pressurizing unit 3, a tube 4, and a pressure-retaining unit 11. The inversion device 1 is a device that injects a pressurized fluid into the pressure vessel 2 and inverts the flexible cylindrical body L1 so that the inside faces the outside. Note that the inversion device 1 does not necessarily have to include the pressure-retaining unit 11. In other words, the pressure-retaining unit 11 is not included in the inversion device 1, and may be considered to be a separate entity from the inversion device 1.

[0011] When inserted into the insertion section 24, the flexible cylindrical body L1 is folded flat with the Y-axis direction as the longitudinal direction, as shown in Fig. 3. The flexible cylindrical body L1 is intended to protect the inner surface T2 of the pipe T1. The pipe T1 is, for example, a water pipe, a sewer pipe, or a gas pipe.

[0012] <Configuration of Pressure Vessel 2> The pressure vessel 2 has a main body 21, a rear end 22, and a front end 23. A rear end 25 is formed in the main body 21, and openings OP1 and OP2 are formed in the rear end 25. As shown in Figure 2, the opening OP1 is closed by the rear end 22, which forms the lid. The rear end 22 is fixed to the rear end 25 with a bolt B1.

[0013] The base portion 7 of the pressure holding unit 11 is sandwiched between the rear end portion 22 and the back portion 25. The bolt B1 is composed of a head portion B2 and a threaded portion B3, and the threaded portion B3 passes through the rear end portion 22 and the base portion 7 and is screwed into the back portion 25. The rear end portion 22 is formed with an insertion portion 24 into which the flexible tubular body L1 is inserted. The insertion portion 24 is an opening, and the shape of the insertion portion 24 is such that the longitudinal direction is in the Y-axis direction. As shown in Figures 1 and 3, the front end portion 23 is a fixing portion to which the tip end L2 of the flexible tubular body L1 is fixed in an annular shape.

[0014] <Configuration of Press-fit Unit 3> The pressurizing unit 3 is connected to the pressure vessel 2 by a tube 4. One end of the tube 4 is connected to the pressurizing unit 3, and the other end of the tube 4 is connected to the opening OP2. The pressurizing unit 3 is a discharge device that discharges a pressurized fluid such as air. The pressurizing unit 3 pressurizes the pressurized fluid into the pressure vessel 2 from the opening OP2 via the tube 4, The flexible cylindrical body L1 is turned over so that the inside faces outward.

[0015] Specifically, when the pressurized fluid is injected into the pressure vessel 2 by the pressurizing unit 3, the flexible cylindrical body L1 is inverted at the folded-back portion L3 of the flexible cylindrical body L1 so that the inside faces out, and the folded-back portion L3 moves in the positive direction of the X-axis. As a result, the flexible cylindrical body L1 wound around the shaft L4 is pulled out in the positive direction of the X-axis, and the flexible cylindrical body L1 is turned inside out.

[0016] The pressurized fluid is heated by the pressurized unit 3, and the heated pressurized fluid is pressurized into the pressure vessel 2. The flexible cylindrical body L1 is turned inside out, and the resin material impregnated inside the flexible cylindrical body L1 is hardened by the pressurized fluid heated by the pressurized unit 3, thereby bonding the inside of the flexible cylindrical body L1 to the inner surface T2 of the pipe T1.

[0017] <Configuration of pressure maintaining unit 11> Fig. 4 is a perspective view showing the configuration of the pressure retaining unit 11 provided in the inversion device 1 shown in Fig. 1. The pressure retaining unit 11 is used in the inversion device 1, and as shown in Figs. 2 and 4, includes a guide member 5, a fixing member 6, a base portion 7, and a pressure retaining member 8. The threaded portions B3 of the multiple bolts B1 are aligned in the Y-axis direction and screwed into the back surface portion 25 on the Z-axis positive side and Z-axis negative side of the opening OP1.

[0018] The guide member 5 is provided in the insertion portion 24, and guides the flexible cylindrical body L1 inserted into the insertion portion 24 to the front end portion 23. The guide member 5 extends in the positive direction of the X-axis from the base portion 7. The guide member 5 has an annular shape, and the outer peripheral surface of the guide member 5 is covered by a pressure retaining member 8. In other words, the pressure retaining member 8 is fitted into the outer peripheral surface of the guide member 5.

[0019] The fixing member 6 is disposed outside the pressure retaining member 8. The fixing member 6 also fixes the pressure retaining member 8 so as to maintain the pressure retaining member 8 in close contact with the flexible cylindrical body L1. The fixing member 6 and the pressure retaining member 8 are fixed to each other with an adhesive. Because the fixing member 6 fixes the pressure retaining member 8, the pressure of the pressure fluid pressurized into the pressure vessel 2 by the press-fitting unit 3 maintains the pressure retaining member 8 in close contact with the flexible cylindrical body L1.

[0020] The shape of the fixing member 6 is a substantially right-angled triangle, but is not limited to this. Two sides of the fixing member 6 that are substantially perpendicular to each other are fixed to the base portion 7 and the pressure retaining member 8, respectively. This allows the pressure retaining member 8 to extend in the positive direction of the X-axis while keeping the size of the fixing member 6 as small as possible, and reduces the manufacturing cost of the fixing member 6.

[0021] The base portion 7 is provided around the insertion portion 24, and a portion of the base portion 7 is exposed to the inside of the pressure vessel 2 from the opening OP1. The fixing member 6 extends from the base portion 7 in the positive direction of the X-axis, and fixes the pressure retaining member 8 so that the pressure retaining member 8 also extends in the positive direction of the X-axis. The length of the fixing member 6 along the X-axis direction is longer than the length of the guide member 5 along the X-axis direction. The length of the pressure retaining member 8 along the X-axis direction is, for example, 100 mm.

[0022] The fixing member 6 fixes the pressure retaining member 8 so that the pressure retaining member 8 extends in the positive direction of the X-axis, and the pressure retaining member 8 is arranged along the flexible cylindrical body L1. This makes it possible to maintain the pressure retaining member 8 in close contact with the flexible cylindrical body L1 due to the pressure of the pressure fluid in the pressure vessel 2.

[0023] The pressure retaining member 8 is provided on the guide member 5 and is formed to extend in the X-axis direction, and is deformed by the pressure of the pressure fluid that is pressurized into the pressure vessel 2 by the pressurizing unit 3 of the inverting device 1, and is tightly attached to the flexible cylindrical body L1. The pressure-retaining member 8 is made of a material that can be deformed by the force of the pressure-retaining member 8, such as a film. The material of the pressure-retaining member 8 is silicon or resin. The pressure-retaining member 8 is annular in shape, and is in close contact with the outer circumferential surface of the flexible cylindrical body L1. This reduces the occurrence of a gap between the pressure-retaining member 8 and the outer circumferential surface of the flexible cylindrical body L1.

[0024] The pressure of the pressurized fluid inside the pressure vessel 2 causes the annular pressure retaining member 8 to adhere tightly to the flexible cylindrical body L1, thereby reducing leakage of the pressurized fluid inside the pressure vessel 2 to the outside of the pressure vessel 2 and preventing a drop in the internal pressure of the pressure vessel 2. This makes it possible to stabilize construction using the flexible cylindrical body L1.

[0025] In addition, in this embodiment, by setting the internal pressure of the pressure vessel 2 to a pressure equal to or higher than a predetermined value, the flexible cylindrical body L1 can be smoothly inverted. In this way, the internal pressure required to invert the flexible cylindrical body L1 can be sufficiently secured inside the pressure vessel 2, and the flexible cylindrical body L1 can be inverted. Furthermore, since leakage of the pressurized fluid inside the pressure vessel 2 to the outside of the pressure vessel 2 is reduced, the time required for construction using the flexible cylindrical body L1 can be shortened and problems that occur when performing construction using the flexible cylindrical body L1 can be eliminated.

[0026] Therefore, the inside of the flexible cylindrical body L1 can be attached to the inner surface T2 of the pipe T1 before the resin material impregnated inside the flexible cylindrical body L1 hardens. Also, since there is no need to increase the internal pressure of the pressure vessel 2 to shorten the time required for construction using the flexible cylindrical body L1, increasing the internal pressure of the pressure vessel 2 can reduce leakage of the pressurized fluid inside the pressure vessel 2 to the outside of the pressure vessel 2.

[0027] As described above, the fixing member 6 fixes the pressure retaining member 8 so as to maintain the pressure retaining member 8 in close contact with the flexible cylindrical body L1. This prevents the pressure retaining member 8 from separating from the flexible cylindrical body L1, and more effectively reduces leakage of the pressurized fluid inside the pressure vessel 2 to the outside of the pressure vessel 2.

[0028] As shown in Figure 4, the fixing member 6 is formed with an exposed portion 61 that exposes the pressure retaining member 8 from the fixing member 6. The exposed portion 61 is the portion of the fixing member 6 that is in contact with the pressure retaining member 8. By forming the exposed portion 61 on the fixing member 6, the exposed portion of the pressure retaining member 8 can be made the portion where the pressure retaining member 8 comes into close contact with the flexible cylindrical body L1 due to the pressure of the pressure fluid inside the pressure vessel 2. Therefore, it is possible to sufficiently maintain airtightness between the pressure retaining member 8 and the flexible cylindrical body L1.

[0029] Furthermore, multiple fixing members 6 are arranged around the insertion portion 24. By arranging multiple fixing members 6 that fix the pressure retaining member 8 along the periphery of the insertion portion 24, the pressure retaining member 8 can be tightly attached along the periphery of the flexible cylindrical body L1. Therefore, leakage of the pressurized fluid inside the pressure vessel 2 to the outside of the pressure vessel 2 can be more effectively reduced.

[0030] It is preferable that a plurality of fixing members 6 are arranged at equal intervals around the periphery of the insertion portion 24. By arranging a plurality of fixing members 6 at equal intervals, it is possible to stably maintain airtightness between the flexible cylindrical body L1 and the entire pressure retaining member 8. It is also preferable that a plurality of fixing members 6 are arranged at equal intervals in the circumferential direction of the pressure retaining member 8.

[0031] <Regarding the inner periphery IP of the pressure-retaining member 8> 5 is a perspective view for explaining the length of the inner periphery IP of the pressure retaining member 8 provided in the pressure retaining unit 11 shown in FIG. 4. As shown in FIG. 5, the pressure retaining member 8 is formed so that the length of the inner periphery IP of the pressure retaining member 8 is equal to or less than the length of the outer periphery OP of the flexible cylindrical body L1 when the insertion part 24 is released from the flexible cylindrical body L1. The inner periphery IP is perpendicular to the X-axis direction. The outer periphery OP is the inner periphery of the cross section of the pressure retaining member 8 when the pressure retaining member 8 is cut along a plane perpendicular to the X-axis direction. The outer periphery OP is the outer periphery of the cross section of the flexible cylindrical body L1 when the flexible cylindrical body L1 is cut along a plane perpendicular to the X-axis direction.

[0032] Since the length of the inner periphery IP of the pressure retaining member 8 is equal to or less than the length of the outer periphery OP of the flexible cylindrical body L1, the pressure retaining member 8 can be tightly attached to the flexible cylindrical body L1 when the flexible cylindrical body L1 is inserted into the insertion part 24. This makes it possible to more effectively reduce leakage of the pressurized fluid inside the pressure vessel 2 to the outside of the pressure vessel 2.

[0033] As described above, by using the inversion device 1, which can reduce the leakage of pressurized fluid inside the pressure vessel 2 to the outside of the pressure vessel 2 and prevent a decrease in the internal pressure of the pressure vessel 2, it is possible to stabilize construction using the flexible cylindrical body L1.

[0034] [Embodiment 2] A second embodiment of the present invention will be described below. For ease of explanation, members having the same functions as those described in the first embodiment will be denoted by the same reference numerals, and their description will not be repeated. FIG. 6 is a perspective view showing the configuration of a pressure-retaining unit 11A provided in an inversion device according to the second embodiment of the present invention. The inversion device according to the second embodiment differs from the inversion device 1 in that it includes a pressure-retaining unit 11A instead of the pressure-retaining unit 11.

[0035] As shown in FIG. 6, pressure retaining unit 11A differs from pressure retaining unit 11 in that it includes a fixing member 6A in addition to fixing member 6. Fixing member 6A is provided at the end of pressure retaining member 8 on the positive X-axis direction side, and fixing member 6A has an annular shape. Fixing member 6A is arranged on the outside of pressure retaining member 8. Fixing member 6A also fixes pressure retaining member 8 so as to maintain a state in which pressure retaining member 8 is in close contact with flexible cylindrical body L1. Fixing member 6A is connected to the end of fixing member 6 on the positive X-axis direction side. Fixing member 6A is fixed around the entire circumference of pressure retaining member 8 with an adhesive.

[0036] The fixing member 6A has an exposed portion 61A that exposes the pressure retaining member 8 from the fixing member 6A. The exposed portion 61A is the portion of the fixing member 6A that is in contact with the pressure retaining member 8. The pressure retaining member 8 is exposed from the exposed portion 61 of the fixing member 6A and the exposed portion 61A of the fixing member 6A.

[0037] By fixing the fixing member 6A around the entire circumference of the pressure retaining member 8, it is possible to more firmly maintain the pressure retaining member 8 in close contact with the flexible cylindrical body L1. Furthermore, when viewed from inside the pressure vessel 2, the end of the pressure retaining member 8 on the positive X-axis side forms the boundary between the pressure retaining member 8 and the flexible cylindrical body L1. Therefore, because the fixing member 6A maintains the end of the pressure retaining member 8 on the positive X-axis side in close contact with the flexible cylindrical body L1, it is possible to more effectively reduce leakage of the pressurized fluid inside the pressure vessel 2 to the outside of the pressure vessel 2.

[0038] [Embodiment 3] A third embodiment of the present invention will be described below. For ease of explanation, members having the same functions as those described in the first and second embodiments will be denoted by the same reference numerals, and their explanations will not be repeated. Fig. 7 is a perspective view showing the configuration of a pressure-retaining unit 11B provided in an inversion device according to the third embodiment of the present invention. The inversion device according to the third embodiment differs from the inversion device 1 in that it includes a pressure-retaining unit 11B instead of the pressure-retaining unit 11.

[0039] As shown in Figure 7, pressure holding unit 11B differs from pressure holding unit 11A in that it does not include fixing member 6. Pressure holding member 8 covers the outer peripheral surface of guide member 5, and fixing member 6A is provided at the end of pressure holding member 8 on the positive X-axis direction side. Pressure holding member 8 is exposed from the exposed portion 61A of the fixing member 6A.

[0040] In pressure retaining unit 11B, compared to pressure retaining units 11 and 11A, the area of ​​the exposed portion of pressure retaining member 8 is larger due to the absence of fixing member 6. Therefore, the area of ​​the portion where pressure retaining member 8 is in close contact with flexible cylindrical body L1 also increases, and the airtightness between pressure retaining member 8 and flexible cylindrical body L1 can be improved.

[0041] 〔summary〕 The pressure retaining unit of aspect 1 of the present invention is a pressure retaining unit used in an inversion device that pressurizes a pressure fluid into a pressure vessel having a rear end where an insertion section into which a flexible cylindrical body is inserted is formed, and a front end where the tip of the flexible cylindrical body is fixed, and inverts the flexible cylindrical body so that the inside becomes the outside, and is configured to include a guide member that is provided in the insertion section and guides the flexible cylindrical body inserted into the insertion section to the front end, and a ring-shaped pressure retaining member that is provided on the guide member and formed to extend in the insertion direction of the flexible cylindrical body, and that deforms due to the pressure of the pressure fluid that is pressed into the pressure vessel by the inversion device and adheres closely to the flexible cylindrical body.

[0042] The pressure retaining unit of aspect 2 of the present invention may be configured in accordance with aspect 1 above, further comprising a fixing member arranged on the outside of the pressure retaining member, and the fixing member may be configured to fix the pressure retaining member so as to maintain the pressure retaining member in close contact with the flexible cylindrical body.

[0043] A pressure-retaining unit according to aspect 3 of the present invention may be configured in the above-mentioned aspect 2 such that the fixing member extends in the insertion direction and fixes the pressure-retaining member so that the pressure-retaining member extends in the insertion direction.

[0044] A pressure-retaining unit according to a fourth aspect of the present invention may be configured in the second or third aspect above such that the fixing member has an exposed portion that exposes the pressure-retaining member from the fixing member.

[0045] A pressure-maintaining unit according to a fifth aspect of the present invention may be configured in the third aspect above, such that a plurality of the fixing members are arranged around the insertion portion.

[0046] The pressure retaining unit of aspect 6 of the present invention may be configured in any of aspects 1 to 5 above, such that the pressure retaining member is formed so that the length of the inner circumference of the pressure retaining member is less than the length of the outer circumference of the flexible cylindrical body when the insertion portion is open.

[0047] The inversion device of aspect 7 of the present invention comprises a pressure vessel having a rear end where an insertion section into which a flexible cylindrical body is inserted is formed, and a front end where the tip of the flexible cylindrical body is fixed; a press-fit unit that pressurizes a pressurized fluid into the inside of the pressure vessel to invert the flexible cylindrical body so that the inside becomes the outside; a guide member that is provided in the insertion section and guides the flexible cylindrical body inserted into the insertion section to the front end; and an annular pressure-retaining member that is provided on the guide member and is formed to extend in the insertion direction of the flexible cylindrical body, and that deforms due to the pressure of the pressurized fluid that is pressed into the inside of the pressure vessel by the press-fit unit to adhere to the flexible cylindrical body.

[0048] The present invention is not limited to the above-described embodiments, and various modifications are possible within the scope of the claims. Embodiments obtained by appropriately combining the technical means disclosed in different embodiments are also included in the technical scope of the present invention. [Explanation of symbols]

[0049] 1. Inverter 2. Pressure vessels 3 Press-fit unit 5 Guide member 6, 6A Fixing member 8 Pressure Retaining Member 11, 11A, 11B Pressure maintaining unit 22 Rear end 23 Front end 24 Insertion section 61, 61A Exposed part IP inner circumference OP outer periphery L1 Flexible cylindrical body L2 tip T1 tube

Claims

1. A pressure holding unit used in an inversion device that injects a pressurized fluid into a pressure vessel having a rear end portion where an insertion portion into which a flexible cylindrical body is inserted is formed, and a front end portion to which a tip of the flexible cylindrical body is fixed, and inverts the flexible cylindrical body so that the inside becomes the outside, a guide member provided in the insertion portion and configured to guide the flexible cylindrical body inserted into the insertion portion to the front end portion; an annular pressure retaining member provided on the guide member, extending in the insertion direction of the flexible cylindrical body, and deformed by the pressure of the pressure fluid injected into the pressure vessel by the inverting device to come into close contact with the entire circumference of the flexible cylindrical body; a fixing member disposed outside the pressure retaining member and extending in the insertion direction, the pressure retaining member is formed so that the length of the inner periphery of the pressure retaining member is equal to or less than the length of the outer periphery of the flexible cylindrical body when the insertion portion is open, the pressure retaining member is fitted onto the outer peripheral surface of the guide member, A pressure-retaining unit characterized in that the fixing member fixes the pressure-retaining member so that the pressure-retaining member maintains a state in which the pressure-retaining member is in close contact with the flexible cylindrical body and extends in the insertion direction.

2. 2. The pressure-holding unit according to claim 1, wherein the fixing member has an exposed portion that exposes the pressure-holding member from the fixing member.

3. 2. The pressure-holding unit according to claim 1, wherein a plurality of the fixing members are arranged around the insertion portion.

4. a pressure vessel having a rear end portion formed with an insertion portion into which a flexible cylindrical body is inserted, and a front end portion to which a tip of the flexible cylindrical body is fixed; a pressurizing unit that pressurizes a pressure fluid into the pressure vessel and inverts the flexible cylindrical body so that the inside faces the outside; a guide member provided in the insertion portion and configured to guide the flexible cylindrical body inserted into the insertion portion to the front end portion; an annular pressure retaining member provided on the guide member, extending in the insertion direction of the flexible cylindrical body, and deformed by the pressure of the pressure fluid pressurized into the pressure vessel by the pressurization unit to come into close contact with the entire circumference of the flexible cylindrical body; a fixing member disposed outside the pressure retaining member and extending in the insertion direction, the pressure retaining member is formed so that the length of the inner periphery of the pressure retaining member is equal to or less than the length of the outer periphery of the flexible cylindrical body when the insertion portion is open, the pressure retaining member is fitted onto the outer peripheral surface of the guide member, An inversion device characterized in that the fixing member fixes the pressure retaining member so that the pressure retaining member maintains a state in which the pressure retaining member is in close contact with the flexible cylindrical body and extends in the insertion direction.

Images