JP4993743B2 - Pressure vessel connection structure - Google Patents

Description

  The present invention relates to a connection structure for connecting a pressure vessel such as a rocket motor case to a support structure.

As this type of pressure vessel connection structure, for example, there are those disclosed in Patent Documents 1 and 2.
In the connection structure disclosed in Patent Document 1, a dome portion that becomes a pressure vessel body is integrally formed with continuous fibers impregnated with a matrix resin, and then a mating resin is impregnated into a fitting portion that fits a flange of the dome portion. After forming the additional winding portion for the mounting surface with other continuous fibers, and curing the impregnated matrix resin, the additional winding portion for the mounting surface is finished to a predetermined dimension, and the mounting portion of the flange is fitted to the portion, Furthermore, it is by performing additional winding for fixing from the attachment part of the flange.

The connection structure disclosed in Patent Document 2 is a carbon fiber having high fiber rigidity formed by being woven into a joint portion with a ring-shaped support structure that is joined along the outer periphery of the pressure vessel at the stage of molding by the filament winding method. A reinforcing layer made of fibers is laminated in the circumferential direction.
Japanese Patent Publication No. 6-69727 JP 2004-132299 A

  In the connecting structure described in Patent Document 1, the load transmission line of the load transmission component formed thinner than the joint of the additional winding portion for fixing is bent at several places, and each bent portion is bent. Stress concentration occurs, which makes it difficult to obtain high mechanical strength.

  On the other hand, the connection structure described in Patent Document 2 is good when the target is achieved with a small amount of the reinforcing layer, but when a large amount of the reinforcing layer is required, the diameter of the rocket motor case is generally large. In this case, there is a problem that the mass of the rocket motor case is increased and the molding process becomes complicated and the manufacturing cost increases.

  Therefore, the present invention provides a pressure vessel connection structure that can firmly connect the support structure and the pressure vessel, and does not cause breakage or poor connection even if the pressure vessel undergoes expansion / contraction deformation due to fluctuations in internal pressure. The purpose is to provide.

  To achieve the above object, the present invention provides a pressure vessel connecting structure that connects a pressure vessel that expands and contracts in accordance with fluctuations in internal pressure and a support structure for supporting the pressure vessel. And a load support member for supporting the load acting on the pressure vessel and the support structure, and an expansion / contraction absorbing member for absorbing expansion / contraction of the load support member accompanying expansion / contraction deformation of the pressure vessel. The load support member and the stretchable absorption member are arranged between the pressure vessel and the support structure with at least a part of both of them being overlapped with each other.

According to the present invention, since the support structure and the pressure vessel are connected by the load support member, the load acting on the support structure and the pressure vessel is supported by the load support member.
On the other hand, as the pressure vessel expands and contracts due to internal pressure, a part of the load support member follows and expands and contracts, and the expansion and contraction absorbing member absorbs expansion and contraction of the load support member.
As a result, the support structure and the pressure vessel can be firmly connected to each other, and even if the pressure vessel undergoes expansion / contraction deformation due to fluctuations in internal pressure, no damage or poor connection occurs.

  The best mode for carrying out the present invention will be described below with reference to the drawings. 1 is a schematic front sectional view showing a part of a rocket to which a pressure vessel connecting structure according to a first embodiment of the present invention is applied, and FIG. 2 is an enlarged sectional view of a portion indicated by an encircling line I in FIG. is there.

  As shown in FIG. 1, a rocket to which a pressure vessel connection structure (hereinafter simply referred to as “connection structure”) according to the first embodiment of the present invention is applied is provided with a motor case 10 as a pressure vessel. Are connected to the head-side and tail-side support structures 20, 30.

  The motor case 10 functions as a propellant case and a combustion chamber, and is made of a carbon fiber reinforced plastic formed by a filament winding method. The motor case 10 has a cylindrical body 11 and a head side of the body 11. The dome-shaped end plate 12 located on the left side (shown in the drawing), the dome-like end plate 13 located on the tail side (the right side in the drawing) of the body 11, and the central axis (machine axis) O1 of the dome-like end plate 13 on the tail side. It has the nozzle 14 to do.

  The head-side support structure 20 serves as an interface with an upper step (not shown). For example, the head-side support structure 20 is an annular shape fitted to the body 11 of the motor case 10 by carbon fiber reinforced plastic that is laminated and formed by a hand layup method or the like. Is formed.

  The tail-side support structure 30 serves as an interface with a lower step (not shown), and in the same manner as the head-side support structure 20, a carbon fiber reinforced plastic laminated and formed by a hand lay-up method or the like is used to form a motor. It is formed in an annular shape that fits to the body 11 of the case 10.

  The head-side support structure 20 is connected to the outer peripheral wall surface 11a of the fuselage 11 closer to the head side, and the tail-side support structure 30 is fixed to the outer peripheral wall surface of the fuselage 11 closer to the tail side. The motor case 10 is fitted and bonded to each other through a connecting structure A1 disposed between the motor 11 and the motor 11.

In FIG. 1, the area | region shown by W1, W2 is a connection part of the head side and tail part side support structures 20, 30 and the motor case 10, and connection structure A1, A1 is arrange | positioned in the area | region.
The connecting portions W1 and W2 are provided with expansion / contraction absorbing members 40 and 40 ′ and load supporting members 50 and 50 ′ that form the connecting structure A1 according to the first embodiment of the present invention.

The load support member 50 connects the motor case 10 and the head-side support structure 20, and supports loads acting on the motor case 10 and the head-side support structure 20, and this embodiment Are formed of a bias woven fabric biased by 45 degrees with respect to the central axis O1 and the circumferential direction.
In addition to the above configuration, the load support member 50 may be configured to be reinforced by forming a UD layer in which fibers are aligned with the central axis O1. In this case, the mechanical strength can be further increased.

The load support member 50 is formed by gently bending a structure-side joint 51 for joining the head-side and tail-side support structures 20, 30 and a container-side joint 52 for joining the motor case 10. It is a toroidal one. In other words, it is bent into a cross-sectional shape that does not cause stress concentration in part.
By gently bending the load supporting member 50 as shown in the present embodiment, it is possible to prevent stress from being concentrated on a part of the load supporting member 50 and to increase the mechanical strength.

  The structure-side joining portion 51 is formed to have a thickness t1 and an outer diameter D1 that contacts the inner wall surface 20a of the head-side support structure 20, the container-side joining portion 42 has a thickness t2, and the motor case. The outer diameter D2 is in contact with the outer peripheral wall surface 11a.

  The thickness t2 of the container-side joint 52 and the adhesion length L1 in the direction along the central axis O1 may be set in consideration of the load acting in the direction α along the central axis O1. Is as follows.

For example, assuming that the load per unit circumferential length is 600 (N / mm) using three load support members 50..., A load of 200 (N / mm) acts on one load support member 50. Become.
In this case, if the thicknesses t1 and t2 of the structure-side joint 51 and the container-side joint 52 are 0.5 to 1 (mm), a load of 200 to 400 (N / mm ² ) acts per unit area. However, the value is sufficient to adopt the existing FRP.
Further, the shear stress generated in the structure-side joining portion 51 is 5 (МPa) when the adhesion length L2 = 40 (mm), and this value can also adopt the existing FRP.

  In the present embodiment, the structure-side joint portion 51 and the container-side joint portion 52 have different thicknesses t1 and t2, but it is needless to say that the same thickness may be used.

  The expansion / contraction absorbing member 40 is for absorbing expansion / contraction of the load support member 50 due to expansion / contraction deformation of the motor case 10, and is made of nitrile rubber in this embodiment, but is formed of, for example, EPDМ or the like. You can also.

  The expansion / contraction absorbing member 40 includes an insertion portion 41 inserted between the inner peripheral wall surface 20a of the head-side support structure 20 and the outer surface 52b of the container-side joint portion 52, and the outer peripheral wall surface 11a of the motor case 10 and the structure. The ring-shaped member is formed with an insertion portion 42 inserted between the inner surface 51a of the body-side joint portion 51.

  The expansion / contraction absorbing member 40 ′ is obtained by shortening the length along the load acting direction α of the expansion / contraction absorbing member 40 described above according to the boundary between the body 11 and the head-side dome-shaped end plate 12, and also supports the load. The member 50 ′ is obtained by extending the structure side joint 51 ′ to the side of the head-side dome-shaped end plate 12.

The expansion / contraction absorbing member 40 and the load support member 50 described above are alternately arranged along the load acting direction α.
In the present embodiment, the adjacent load support members 50 and 50 are arranged at a predetermined interval P1, and the expansion / contraction absorbing member 40 and the load support member 50 are at least a part of both. Are disposed between the motor case 10 and the head-side support structure 20.

Specifically, the elastic absorption member 40 is provided between the inner surface 51 a of the structure-side joint 51 and the motor case 10 and between the outer surface 52 b of the container-side joint 52 and the inner wall 20 a of the head-side support structure 20. , 40 are inserted.
In other words, the expansion / contraction absorbing member 40 and the load support member 50 are interposed between the inner wall surface 20a of the head-side support structure 20 and the outer peripheral wall surface 11a of the motor case 10 so as to overlap each other.

The operation of the connection structure A1 described above is as follows.
When the propellant burns and the motor case 10 expands as the internal pressure increases, the bulges in the radial direction at the connecting portions W1 and W2 between the head-side support structure 20 and the tail-side support structure 30 are as follows. Both are restrained by the support structures 20 and 30 connected and coupled along the outer periphery of the body 10 of the motor case 10.

  In addition, the motor case 10 expands also in the load acting direction α in each of the connecting portions W1 and W2, and the container side joint 52 also expands along with this expansion. Further, the extension deformation of the container side joint portion 52 is absorbed by the deformation of the expansion and contraction absorbing member 40, so that high stress is not transmitted to the head side and tail side support structure 30.

  Furthermore, since the load support member 50, and therefore the container side joint portion 52, is lower in both thickness and rigidity than the head side support structure 20, the stress generated in the connecting portions W1 and W2 is low. Even if the internal pressure of the case 10 is equal to or higher than the guaranteed pressure, it is possible to prevent peeling or breakage between the head side and tail side support structures 20 and 30.

  Furthermore, since the expansion / contraction absorbing member 40 and the load support member 50 described above can be easily mounted by simply fitting and bonding to the motor case 10 in order, the working cost can be reduced.

  Next, the connection structure according to the second embodiment will be described with reference to FIG. FIG. 3 is a partial enlarged cross-sectional view of the connection structure A2 according to the second embodiment, and corresponds to a portion indicated by an encircling line I in FIG. In addition, about the thing equivalent to what was demonstrated in embodiment mentioned above, the code | symbol same as them is attached | subjected and detailed description is abbreviate | omitted.

  The connection structure A2 according to the second embodiment includes a load support member 60 and a stretchable absorption member 70, which are configured differently from those described above, by superimposing at least a part of both on the motor case 10 and the head. It is disposed between the head side and tail side support structures 20 and 30 and the motor case 10.

The load support member 60 has a structure-side joint 61 for joining to the head-side and tail-side support structures 20 and 30 and a container-side joint 62 for joining to the motor case 10 via an inclined part 63. It is a ring-shaped one that is gently bent. In other words, the cross-sectional shape does not cause stress concentration.
The structure-side joining portion 61 and the container-side joining portion 62 have the same length in the load acting direction α.

  The structure-side joint 61 is formed with an outer diameter D1 that contacts the inner wall surface 20a of the head-side support structure 20, and the container-side joint 62 is an outer diameter that contacts the outer peripheral wall 11a of the motor case 10. D2 is formed.

In the present embodiment, adjacent load support members 60, 60 are arranged in close contact with each other.
Specifically, the structure side joints 61 and 61 and the container side joints 62 and 62 of the adjacent load support members 60 and 60 are arranged in close contact with each other. In other words, the structure-side joints 61 and the container-side joints 62 of the adjacent load support members 60 and 60 are arranged to face each other.
Thereby, between the load supporting members 60 and 60 adjacent to each other, an annular space β having a parallelogram-shaped cross section is formed by the structure-side joint portions 61 and 61, the container-side joint portions 62 and 62, and the inclined portions 63 and 63. A compartment is formed.

The expansion / contraction absorbing member 70 has an annular shape surrounding the motor case 10 formed in a cross-sectional parallelogram corresponding to the annular space β defined by the adjacent load support members 60, 60.
The stretchable and absorbing members 70 are arranged so as to overlap with the annular space β.

  The stretch absorbing member 70 ′ is obtained by shortening the length along the action direction α of the load of the stretch absorbing member 70 described above according to the boundary between the body 11 and the head-side dome-shaped end plate 12. The stretch absorbing member 70 ″ is obtained by extending the length along the load acting direction α of the stretch absorbing member 70 described above to the tail side.

  The connection structure according to the third embodiment will be described with reference to FIG. FIG. 4 is a partial enlarged cross-sectional view of the connection structure A3 according to the third embodiment, and corresponds to a portion indicated by an encircling line I in FIG. In addition, about the thing equivalent to what was demonstrated in embodiment mentioned above, the code | symbol same as them is attached | subjected and detailed description is abbreviate | omitted.

  The connection structure A3 according to the third embodiment has a configuration in which the load support members 70 and 70 described in the second embodiment are arranged with a predetermined dimension P2 therebetween, and accordingly, the expansion and contraction is absorbed. The structure of the member 80 is varied.

The expansion / contraction absorbing member 80 has a thickness t3 in which the outer peripheral surface 80a and the inner peripheral surface 80b abut against the inner surface 20a of the head-side support structure 20 and the outer peripheral wall surface 11a of the motor case 10, and a length L2 is set. The ring-shaped member is formed in a substantially parallelogram with a cross section set to a value corresponding to the distance between the load supporting members 70 and 70.
In this case, since the thickness dimension of the expansion / contraction absorbing member 80 can be set large, it is possible to cope with large expansion / contraction of the load support member 60.

  A connection structure according to the fourth embodiment will be described with reference to FIG. FIG. 5 is a partial enlarged cross-sectional view of the connection structure A4 according to the fourth embodiment, and corresponds to a portion indicated by an encircling line I in FIG. In addition, about the thing equivalent to what was demonstrated in embodiment mentioned above, the code | symbol same as them is attached | subjected and detailed description is abbreviate | omitted.

The connection structure A4 according to the fourth embodiment employs a load support member 90 and a stretchable absorption member 100 having different configurations from those described in the above embodiments.
The load support member 90 includes a structure-side joint 91 for joining the head-side and tail-side support structures 20, 30, a container-side joint 92 for joining the motor case 10, and the structures-side, container The ring-shaped member is formed by gently bending an intermediate portion 93 having a predetermined step between the side joint portions 91 and 92 and parallel to each other. In other words, the cross-sectional shape does not cause stress concentration in part.

The structure-side joining portion 91, the container-side joining portion 92, and the intermediate portion 93 have the same length in the load acting direction α.
The predetermined step is a constant interval t5 between the inner surface 91a of the structure-side joining portion 91 and the outer surface 93b of the intermediate portion 93, and between the inner surface 93a of the intermediate portion 93 and the outer surface 92b of the container-side joining portion 92. This is due to the provision of
Adjacent load support members 90, 90 are arranged such that the structure side joining portion 91 and the container side joining portion 92 are opposed to each other with a predetermined interval.

The expansion / contraction absorbing member 100 is for absorbing expansion / contraction of the load support member 90 due to expansion / contraction deformation of the motor case 10, and includes the outer surface 93 b of the intermediate portion 93 and the inner surface 20 a of the head-side support structure 20. An annular shape having insertion portions 100a, 100b, 100c extending between the outer surface 92b of the container side joint 92 and the structure side joint 91 and between the inner surface 92a of the container side joint 92, respectively. Is.
In other words, in the present embodiment, the structure is such that the stretch absorbing members 100 and 100 are interposed between the outer side and the inner side of the intermediate portion 93, so that the expansion and contraction of the motor case 10 can be absorbed more satisfactorily.

  A connection structure according to the fifth embodiment will be described with reference to FIG. FIG. 6 is a partial enlarged cross-sectional view of the connection structure A5 according to the fifth embodiment, and corresponds to a portion indicated by an encircling line I in FIG. In addition, about the thing equivalent to what was demonstrated in embodiment mentioned above, the code | symbol same as them is attached | subjected and detailed description is abbreviate | omitted.

  The connection structure A5 according to the fifth embodiment has a configuration in which two types of load support members bent in different shapes are combined. In the present embodiment, the load supporting member 90, the load supporting member 110, and the expansion / contraction absorbing member 120 described in the fourth embodiment are combined.

  The load support member 110 includes a structure-side joint 111 for joining with the head-side and tail-side support structures 20, 30, a container-side joint 112 for joining with the motor case 10, and these structures-side, container The ring-shaped member is formed by gently bending an intermediate portion 113 having a predetermined step between the side joint portions 111 and 112 and parallel to each other. In other words, the cross-sectional shape does not cause stress concentration in part.

  The structure-side joint portion 111 has a dimension obtained by adding the dimensions of the container-side joint portion 92 and the intermediate portion 93 of the load support member 90. The intermediate portion 113 and the container-side joint portion 112 are formed of the load support member. It is formed in the same dimensions as 90 container side joints 92 and the like.

  Adjacent load supporting members 110 and 110 are arranged in a state where the inner surface 111a of the other structure side joint 111 is in contact with the outer surface 113b of the intermediate portion 113 of the one. With this configuration, the rigidity in the acting direction α of the load can be made constant.

  The expansion / contraction absorbing member 120 is for absorbing expansion / contraction of the load support member 110 due to expansion / contraction deformation of the motor case 10, and includes an inner surface 111a of the structure-side joint portion 111 and an outer surface 112b of the container-side joint portion 112 described above. , And between the inner surface 113 a of the intermediate portion 113 and the outer peripheral wall surface 11 a of the motor case 10, are annular shapes having insertion portions 120 a and 120 b respectively extending.

The present invention is not limited to the above-described embodiments, and the following modifications can be made.
In the above-described embodiment, the example applied to a pressure vessel such as a motor case of a rocket has been described as an example. However, the embodiment can also be applied to other pressure vessels.

  In the embodiment described above, an example in which a single stretch absorbing member is disposed between two adjacent load support members has been described, but two or more stretch absorbing members may be interposed.

In the above-described embodiment, the example in which the arrangement interval of the load support members is made constant has been described. However, the arrangement interval may be varied according to the stress difference in the connecting portion of the pressure vessel.
For example, the arrangement interval of the load support members is narrowed in a portion where the stress is high, and the arrangement interval of the load support members is widened in a portion where the stress is low.

  In the above-described embodiment, except for those arranged on the head side and the tail side, the stretch absorbing members and the load supporting members arranged between them are arranged in the same form with a constant interval. Although the example has been described, the dimensions of the stretch absorbing member and the load supporting member in the load acting direction may be varied according to the stress difference of the pressure vessel in the load acting direction.

  In the embodiment described above, the motor case made of carbon fiber reinforced plastic formed by the filament winding method has been described as an example. However, the present invention is not limited to this, and it can be applied to a metal or synthetic resin.

It should be noted that the dimensions and shapes of the respective parts such as the thickness and the adhesion length shown in the respective drawings are simplified or exaggerated for the purpose of explanation, and are intended to be limited to the dimensions and shapes explicitly shown in the respective drawings. It is not a thing.
Although a plurality of embodiments have been described in detail, in any case, each configuration described in each of the above embodiments is not limited to being applied only to each of the embodiments, and the configuration described in one embodiment. Is applied mutatis mutandis or applied to other embodiments, and further, it can be arbitrarily combined.

It is a general | schematic front sectional view which shows a part of rocket to which the connection structure of the pressure vessel concerning 1st embodiment of this invention is applied. FIG. 2 is an enlarged cross-sectional view of a portion indicated by a surrounding line I in FIG. It is a partial expanded sectional view of the connection structure which concerns on 2nd embodiment, and is corresponded in the part shown by the surrounding line I in FIG. It is a partial expanded sectional view of the connection structure which concerns on 3rd embodiment, and is equivalent to the part shown by the surrounding line I in FIG. It is a partial expanded sectional view of the connection structure which concerns on 4th embodiment, and is corresponded in the part shown by the surrounding line I in FIG. It is a partial expanded sectional view of the connection structure which concerns on 5th embodiment, and is corresponded in the part shown by the surrounding line I in FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Pressure vessel 20, 30 Support structure 40,70,80,100,120 Stretch-absorption member 50,60,90,110 Load support member 51,61,91,111 Structure side junction part 52,62,92,112 Container Side joint α Load acting direction

Claims (11)

In the connecting structure of the pressure vessel that connects the pressure vessel that expands and contracts according to the fluctuation of the internal pressure and the support structure for supporting the pressure vessel,
A load support member for connecting the pressure vessel and the support structure, and supporting a load acting on the pressure vessel and the support structure;
An expansion / contraction absorbing member for absorbing expansion / contraction of the load supporting member accompanying expansion / contraction deformation of the pressure vessel,
A connecting structure for a pressure vessel, wherein the load support member and the expansion and contraction absorbing member are disposed between the pressure vessel and the support structure with at least a part of both of them being overlapped with each other.   2. The pressure vessel connection structure according to claim 1, wherein a plurality of load support members are arranged at regular intervals along the direction of load application.   3. The pressure vessel connection structure according to claim 2, wherein the load supporting members and the expansion and contraction absorbing members are alternately arranged along the direction of load application.   4. The pressure vessel connection structure according to claim 2, wherein adjacent load supporting members are arranged in close contact with each other.   The load support member is characterized in that a structure-side joint for joining to a support structure and a container-side joint for joining to a pressure vessel are bent so as not to cause stress concentration. The connection structure of the pressure vessel of any one of Claims 1-4.   6. The pressure vessel connection structure according to claim 5, wherein an expansion / contraction absorbing member is interposed between the structure side joint portion of the load support member and the pressure vessel.   The connecting structure for a pressure vessel according to claim 5 or 6, wherein an expansion / contraction absorbing member is interposed between the container-side joint portion of the load support member and the support structure.   The stretchable absorbing member is interposed between the container-side joint portion of one of the two adjacent load support members and the structure-side joint portion of the other one of claims 5 to 7. The pressure vessel connection structure according to claim 1.   The pressure vessel connection structure according to any one of claims 2 to 8, wherein a single expansion and contraction absorbing member is disposed between two adjacent load support members.   The connection of pressure vessels according to any one of claims 2 to 9, wherein the arrangement interval of the load support members is varied according to the stress difference in the connection portion between the support structure and the pressure vessel. Construction.   11. The pressure vessel connecting structure according to claim 1, wherein the load supporting member and the expansion and contraction absorbing member are formed in an annular shape surrounding the pressure vessel.

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