Device for separating two rocket stages

Abstract

The invention relates to a device for separating a first rocket stage from a second rocket stage, having a bolt assembly (A) which can be connected to the first rocket stage and a receiving assembly (B) which can be connected to the second rocket stage, wherein the bolt assembly (A) has a bolt (1) with a neck (13) and a mushroom-shaped widened free end (15) connected thereto, and a transition area (14) between the neck (13) and the extended end (15) is clamped and secured in a connected state by a plurality of locking elements (10) in the receiving assembly (B), and the locking elements (10) are displaced radially outwards with respect to the bolt (1) in a disconnected state, as a result of which the mushroom-shaped widened end (15) is released and the bolt assembly (A) can be withdrawn from the receiving assembly (B). The disadvantage here is that the force transmission is not optimal and therefore very large separating devices must be used. The object of further developing a device for separating a first rocket stage from a second rocket stage in such a manner that a high transmission of force takes place and at the same time rapid release is ensured is achieved by the fact that each locking element (10) has two end surfaces (10b) between which there is a circumferential surface (16) with a convex barrel shape and the transition area (14) of the bolt (1) to each locking element (10) has a complementary abutment surface (1b) to this convex barrel shape.

Description

DEVICE FOR SEPARATING TWO ROCKET STAGESDESCRIPTION

[0001] The invention relates to a device for separating a first rocket stage from a second rocket stage according to the preamble of claim 1.

[0002] In multi-stage rockets such as those used for space exploration and for launching satellites into space, the first rocket stage, which usually has several high-power engines and large fuel tanks, must be disconnected after reaching a certain altitude, i.e. when the fuel has been used up, so that the rocket can continue its flight with the remaining second stage, which has a lower motorization. The separated rocket stage falls back to earth.

[0003] For this purpose, it is important to separate the first rocket stage completely and safely from the second rocket stage at a certain point in time. This requires special separation devices which, on the one hand, guarantee a secure connection between the two rocket stages during launch and during operation of the first rocket stage and, on the other hand, can separate the connection so quickly and completely under load that the first rocket stage separates completely from the second rocket stage.

[0004] For this purpose, it is common in the prior art to use so-called quick-change modules, such as those marketed by the Tooling Tech Group under the “Segen” brand. Such quick-change systems have a bolt assembly connectable to the first rocket stage and a receiving assembly connectable to the second rocket stage, wherein the bolt assembly has a bolt with a neck and an adjoining mushroom-shaped extended free end, and a transition area between the neck and the extended end is clamped and secured in a connected state by a plurality of locking elements in the receiving assembly and the locking elements are displaced radially outwards with respect to the bolt in a disconnected state, whereby the mushroom-shaped extended endis released and the bolt assembly can be withdrawn from the receiving assembly, and thus also the first rocket stage from the second rocket stage.

[0005] Locking elements with a spherical shape are the industry standard and are referred to as “ball locks”. The spherical locking elements interact with the complementary abutment surfaces either in the form of points or lines. In addition, the lengths of the line contacts are relatively short.

[0006] The disadvantage of these known devices is that the force transmission is not optimal and therefore very large separating devices must be used, which increase the weight of the rocket and worsen the aerodynamics, as these are located in the area of the outside of the connection between the two rocket stages.

[0007] The object is therefore to further develop a device for separating a first from a second rocket stage in such a manner that a high force transmission takes place and at the same time a quick release is ensured.

[0008] This object is achieved with the characterized features of claim 1. Advantageous embodiments can be taken from the sub-claims.

[0009] According to the invention, each of the locking elements has two end surfaces between which there is a circumferential surface with a convex barrel shape and the transition area of the bolt to each locking element has a complementary abutment surface to this convex barrel shape. The term barrel shape can also be referred to as drum shape. It is substantially the bulbous, outwardly directed design of the locking elements.

[0010] The use of barrel-shaped locking elements means that the interaction between the locking elements and the bolts, which is furthest inwards, can be designed in a flat shape. The resulting interaction surface allows significantly higher clamping forces than would be possible with knownspherical locking elements, as the local maximum curvatures are significantly greater with barrels than with spheres.

[0011] The use of barrel-shaped locking elements also makes it possible to create a line contact between the locking elements and the piston in such a manner that the piston can be designed as a purely rotationally symmetrical component. This allows a smaller construction volume and a lower weight than would be possible with other forms of locking elements.

[0012] Preferably, the locking elements are mounted in openings in an anchor element of the receiving assembly (B).

[0013] Preferably, on each of the two end surfaces of each locking element, the bulged barrel shape of the circumferential surface is extended over an angular area of the end surfaces, forming finger elements projecting beyond the respective end surfaces.

[0014] The finger-shaped protrusions on the end surfaces of the barrelshaped locking elements prevent the locking elements from falling through the anchor element when open. These finger-shaped forms are complex to manufacture. They make it possible to maximize the interaction line lengths between the locking elements, the anchor element and the piston as well as the interaction surface between the locking elements and the bolt. The combination of the barrel shape of the locking elements and the finger-shaped protrusions makes it possible to maximize power transmission while minimizing the construction volume and weight.

[0015] Preferably, the mentioned angle area of the end surfaces is between 5 and 180 degrees, at best between 60 and 120 degrees.

[0016] Preferably, the bolt has a multi-edge element which, when connected, engages in a corresponding anti-rotation element of the receiving assembly.

[0017] The multi-edge element in conjunction with the anti-rotation element of the receiving assembly allow the nut to be tightened without additional forces and stresses arising from the rotation of the bolt relative to the anchor element.

[0018] Preferably, the anti-rotation element is connected to the anchor element in a form-locking manner.

[0019] Preferably, the receiving assembly has a housing in which a potshaped piston is displaceably mounted, wherein the piston presses the locking elements against the transition area with an area of smaller internal diameter in the connected state and is displaced within the housing in the disconnected state with respect to the connected state and receives the outwardly pressed locking elements in a second area of larger internal diameter, whereby the end of the bolt is released.

[0020] Preferably, the piston can be moved in a sealing manner relative to the housing and is supported with an inner bottom side against an underside of the anchor element via a coil spring, wherein the piston is transferred from the connected to the disconnected state by applying pressure to the space between the housing and piston, compressing the coil spring.

[0021] Preferably, the pressure is exerted by a pneumatic or hydraulic pump via a connection piece located in the housing.

[0022] Preferably, the anchor element has an annular damping element for damping the impact of the free end of the piston during the transition from the connected to the disconnected state.

[0023] Preferably, the anchor element is screwed into the housing.

[0024] An embodiment of the invention is explained in more detail below with reference to the accompanying drawings. In the figures:Fig. 1 is a perspective view of a bolt assembly A separated from the receiving assembly B.Fig. 2 is an exploded view as shown in Fig. 1 ;Fig. 3 is a perspective view of the locking element shown in Fig. 2 (a) and this locking element in longitudinal section (b) and in cross-section (c);Fig. 4 is a cross-sectional view of the bolt assembly engaged with the receiving assembly (a) and the disengaged bolt assembly (b);Fig. 5 is an illustration of the interlocking of the locking elements with the complementary abutment surfaces, partly shown in section;Fig. 6 is an illustration as shown in Fig. 5 with the locking elements fully drawn in and without housing and damping element.

[0025] Fig. 1 shows a perspective view of a bolt assembly A that is separate from the receiving assembly B. The connection between the receiving assembly B and the bolt assembly A with the rocket stages is not shown. The receiving assembly B can, for example, be connected to the first (lower) rocket stage and the bolt assembly (A) to the second (upper) rocket stage. It should be noted here that several combinations of bolt assembly A and receiving assembly B are generally used around the circumference of the rocket stages, e.g. two, four or more combinations of these two assemblies. During the separation of the two rocket stages, it is important that all combinations of bolt assemblies A and receiving assemblies B are separated exactly at the same time, but this is not explained in detail in the following description, as it only refers to one unit of a bolt assembly A and a receiving assembly B.

[0026] The receiving assembly B has a housing 4, which is substantially cylindrical. A connection piece 5 for a pneumatic or hydraulic pressure supply, which is not shown in detail, is located in the lower area of the housing 4. It should be noted that this hydraulic pressure supply can be used to introduce either hydraulic or pneumatic pressure into the housing 4, which is preferablydone intermittently. The generation of this pressure is not described in more detail below.

[0027] At the upper end of the housing 4 there is an anchor element 11 screwed into the housing 4, the inside of which is octagonal and accommodates an anti-rotation element 12, the inside of which is also octagonal. On the left and right outside the top of the housing 4 are screws 6, which are only shown schematically in Fig. 1 , i.e. without threads.

[0028] Above the receiving assembly B is the bolt assembly A, which has a bolt 1 with a multi-edge element 1a. As can be seen from Fig.2, the bolt 1 has a neck 13, wherein contact surfaces 1 b are arranged on the mushroom-shaped widened free end 15 of the bolt 1, namely eight bearing surfaces 1b in the embodiment example shown, evenly around the circumference of the mushroom-shaped widened end 15 of the bolt 1 , and on the mushroom-shaped widening, so that the abutment surfaces 1b point upwards, i.e. away from the receiving assembly B. There is also a washer 2 and a nut 3 on the bolt 1.

[0029] The entire arrangement is shown in an exploded view in Fig. 2. Also shown here is the receiving assembly B with the housing 4 and the screws 6, as well as with the connection piece 5 for the pneumatic or hydraulic pressure supply. Also shown is the already described anchor element 11 with the antirotation element 12, with internal octagon, so that the anti-rotation element 12 can be accommodated in the anchor element 11 in a form-locking manner. The locking elements 10 are partially installed and partially removed in the exploded view. They form the connection between the receiving assembly B and the bolt assembly A. When installed, these locking elements 10 come to rest against the abutment surfaces 1b. This means that there are just as many locking elements 10 as abutment surfaces 1b.

[0030] Between the housing 4 and the anchor element 11 there is a piston 7, the outer side of which, starting from the housing 4, is initially cylindrical, thenwidens continuously and then becomes cylindrical again with a larger outer diameter. The piston 7 is sealed against the housing 4 with an O-ring 7b. The piston 7 accommodates a coil spring 8, which acts between the inner base of the piston 7 and the anchor element 11.

[0031] The design of the locking elements 10 is shown in Fig. 3. Here, illustration (a) shows the locking element 10 in perspective view, illustration (b) shows the locking element 10 in longitudinal section and illustration (c) shows the locking element 10 in cross-section.

[0032] The locking element 10 is designed in such a manner that it has two end surfaces 10b, between which there is a circumferential surface 16 with a convex barrel shape, which could also be referred to as a barrel shape or belly shape. This is best illustrated in Fig. 3 (a). It can be seen from all the figures in Fig.3 that each locking element 10, in a preferred embodiment which is not essential to the invention, extends the convex barrel shape, which can also be referred to as a bulged barrel shape, of the circumferential surface 16 at each of its two end surfaces 10b over an angular area of the two end surfaces 10b, forming finger elements 10a projecting beyond the respective end surfaces 10b. These finger elements 10a are used to secure the locking elements 10. The radius R4 shown is the radius of the barrel-shaped circumferential surfaces 16 of the locking elements 10 and the radius R5 shown is the radius describing the body diameter of the locking elements 10, wherein the radius R5 is less than the radius R4. The axis of radius R4 is perpendicular to the axis of radius r5 and these two axes have no point of contact. The finger elements 10a on the end surfaces 10b of the barrelshaped locking elements 10 prevent the locking elements 10 from falling through the anchor element 11 in the open state. These finger elements 10a are complex to manufacture and make it possible to maximize the interaction line lengths between the locking elements 10, the anchor element 11 and the piston 7, as well as the interaction surface between the locking elements 10 and the bolt 1. The combination of the barrel shape of the locking elements 10 with the protrudingfinger elements 10a makes it possible to maximize the power transmission and at the same time minimize the construction volume and weight.

[0033] Fig. 4 shows a cross-sectional view of the bolt assembly A engaged with the receiving assembly B in part figure (a) and the disengaged bolt assembly A in part figure (b). First, the latched state is described in subfigure (a). The housing 4 of the receiving assembly B is shown with the piston 7 inside and a damping element 9, which damps the impact of the piston 7 when the device is opened. The piston 7 is sealed against the housing 4 with an 0-ring 7c. The piston 7 has an internal recess 7b above the 0-ring 7c, which runs along the entire circumference and forms a kind of internal groove that widens the inside of the piston 7 at this point so that the locking elements 10 can be accommodated in this area when disengaged. A coil spring 8 acts between the lower inside of the piston 7 and the anchor element 11 , the force of which pushes the anchor element 11 away from the underside of the piston 7, i.e. a maximum distance is maintained between the underside of the piston 7 and the anchor element 11.

[0034] On the side of the bolt assembly A, the bolt 1 is shown with the mushroom-shaped extension at its lower end 15 and the abutment surfaces 1b located on it. Also shown is the multi-edge element 1a on the bolt 1, which engages in the inner octagon of the anti-rotation element 11. In addition, the washer 2 and the nut 3 on the side of the bolt 1 are again in contact with the flange 19, which remains loosely connected to the bolt 1 and the nut 3 after the separation mechanism has been opened, and the underlying flange 20, which is firmly connected to the housing 4 by the screws 6. The locking elements 10 described in detail with reference to Fig. 3 are located between the receiving assembly B and the bolt assembly A, in such a manner that they rest on the one hand against the abutment surfaces 1b of the mushroomshaped extension at the end 15 of the bolt 1 and on the other hand against the upper inner side of the piston 7. In this manner, a stable connection between bolt assembly A and receiving assembly B, mediated via the locking elements 10, is ensured in the state shown in Fig.4(a). The first angle 17 drawn betweenthe bearing surface of the anchor element 11 and the sliding surface, on which the locking elements 10 can move in order to release the mechanism, is also drawn, as is the second angle 18 between the sliding surface of the anchor element 11 and the barrel-shaped interaction surfaces 1d of the bolt 1. The first angle 17 is selected so that there is an optimum ratio between size, weight and the clamping force to be absorbed and the second angle 18 is selected to be as small as possible in order to keep the radial force on the piston 7 as low as possible. However, this second angle 18 is so large that there is no selflocking of the locking element 10 when the mechanism is opened. The multiedge element 1a on the bolt 1 in conjunction with the anti-rotation element 12 allows the nut 3 to be tightened without additional forces or stresses arising from the rotation of the bolt 1 relative to the anchor element 11.

[0035] The protruding finger elements 10a make it possible to maximize the interaction line lengths between the locking elements 10, the anchor element 11 and the piston 7, as well as the interaction surface between the locking elements 10 and the bolt 1. The combination of the barrel shape of the locking elements 10 and the finger elements 10a makes it possible to maximize the power transmission and at the same time minimize the construction volume and weight.

[0036] The detached illustration of the receiving assembly B and piston assembly A is shown in part figure (b) of Fig.4. The spring 8, which would have to be shown compressed in this case, is not shown here. It can be seen that the piston crown (shown below) is now at a distance from the base of the housing 4. This distance was created by applying either pneumatic or hydraulic pressure to the connecting piece 5 so that the pressure inside the housing 4 between the inside of the housing and the outside of the piston 7 was so high that the spring 8 was compressed. Thanks to the O-rings 7c, this is possible without compressed air or hydraulic fluid escaping between housing 4 and piston 7.

[0037] In the illustration b (Fig. 4) it can be seen that the locking elements 10 are now no longer pressed against the narrowest uppermost point of the piston7, but can move outwards into the recess 7b on the inside of the piston 7 due to the upward movement of the piston 7 in the direction of the bolt element A. In this manner, the inner diameter of the circle formed on the locking elements 10 increases beyond the outer diameter of the mushroom-shaped extension at the end 15 of the piston 1, so that this mushroom-shaped extension can slide upwards out of the entire receiving assembly through the locking elements 10, wherein the flange 19 is no longer shown in partial figure (b) of Fig. 4, as it is pulled off upwards together with the piston 1 , the washer 2 and the nut 3. This pulling off is supported by the acceleration effect of the thrust of the engine of the second rocket stage on which the bolt assembly (A) is located.

[0038] The exact geometry of the individual radii of the components used is shown in Fig. 5, which shows the interlocking of the locking elements 10 with the complementary abutment surfaces 1b. Also shown here is the bolt 1 with the multi-edge element 1a arranged thereon on the one hand, as well as the complementary abutment surfaces 1b at the mushroom-shaped widened end 15 of the bolt 1 , which interact with the locking elements 10, wherein the end surfaces 10b and the finger elements 10a are also shown here. Also shown are the anchor element 11, the damping element 9, the housing 4, the piston 7 with the O-ring 7c and the coil spring 8. The position shown corresponds to the locked state between receiving assembly B and bolt assembly A. The radius R1 shown is the radius of the inner cylinder surface of the piston 7, which forms a line contact with the locking element 10. The second radius R2 is the radius of the inner cylindrical surface of the anchor element 11 , which forms a line contact with the locking element 10. The third radius R3 is the radius of the barrel-shaped interaction surfaces 1 b of the bolt 1 , which form a large surface contact with the locking elements 10. The fourth radius R4 is the radius of the barrel-shaped outer surfaces of the locking elements 10. The fifth radius R5 is the body diameter of the locking elements 10, wherein the fifth radius R5 should be smaller than the fourth radius R4, as already described. With regard to the remaining radii R1 , R2, R3 and R4, these should be equal or approximately equal. The use of barrelshaped locking elements 10 with the condition that the radius R5 is smaller thanthe radius R4 makes it possible to create a line contact between the locking elements 10 and the piston 7 in such a manner that the piston 7 can be designed as a purely rotationally symmetrical component. This allows a lower construction volume weight than would be possible with other forms of locking elements 10.

[0039] Finally, Fig. 6 shows a representation as shown in Fig. 5 with the locking elements 10 fully drawn in and without housing 4. Also shown here are the coil spring 8, the seal 7c, the recess 7b within the housing 7, the anchor element 11 and the anti-rotation element 12 as well as the piston 1 with multiple multi-edge element 1a. For a more detailed description of the shape of the locking elements 10, reference is made to the description of Fig. 3.

Claims

Claims1. A device for separating a first rocket stage from a second rocket stage, having a bolt assembly (A) connectable to the first rocket stage and a receiving assembly (B) connectable to the second rocket stage, wherein the bolt assembly (A) has a bolt (1 ) with a neck (13) and an adjoining mushroom-shaped extended free end (15) and a transition area (14) between the neck (13) and the widened end (15) is clamped and secured in a connected state by a plurality of locking elements (10) in the receiving assembly (B), and the locking elements (10) are displaced radially outwards with respect to the bolt (1) in a disconnected state, as a result of which the mushroom-shaped widened end (15) is released and the bolt assembly (A) can be withdrawn from the receiving assembly (B), characterized in that each locking element (10) has two end surfaces (10b), between which there is a circumferential surface (16) with a convex barrel shape, and the transition area (14) of the bolt (1) to each locking element (10) has a complementary abutment surface (1 b) to this convex barrel shape.

2. The device according to claim 1, characterized in that the locking elements (10) are mounted in openings of an anchor element (11 ) of the receiving assembly (B).

3. The device according to claim 2, characterized in that the bulged barrel shape of the circumferential surface (16) of each locking element (10) extends at each of its two end surfaces (10b) over an angular area of the end surfaces (10b), forming finger elements (10a) projecting beyond the respective end surfaces (10b).

4. The device according to claim 3, characterized in that the angle area lies between 5 and 180 degrees, preferably between 60 and 120 degrees.

5. The device according to any of the preceding claims, characterized in that the bolt (1) has a multi-edge element (1a) which, in the connectedstate, engages in a corresponding anti-rotation element (12) of the receiving assembly (A).

6. The device according to claim 5, characterized in that the anti-rotation element (12) is connected to the anchor element (11 ) in a form-locking manner.

7. The device according to any of claims 2 to 6, characterized in that the receiving assembly (B) has a housing (4) in which a cup-shaped piston (7) is displaceably mounted, wherein the piston (7), in the connected state, presses the locking elements (10) against the transition area (14) with an area of smaller internal diameter and, in the disconnected state, is displaced within the housing (4) relative to the connected state and receives the outwardly pressed locking elements (10) in a second area of larger internal diameter, whereby the end (15) of the bolt (1) is released.

8. The device according to claim 7, characterized in that the piston (7) can be moved in a sealing manner relative to the housing (4) and is supported with an inner bottom side against an underside of the anchor element (11) via a coil spring (8), wherein the piston (7) is transferred from the connected to the disconnected state by applying pressure to the space between the housing (4) and the piston (7) and the coil spring (8) is compressed in the process.

9. The device according to claim 8, characterized in that the pressure is exerted by a pneumatic or hydraulic pump via a connecting piece (5) located in the housing (4).

10. The device according to any of claims 7 to 9, characterized in that the anchor element (11) comprises an annular damping element (9) for damping the impact of the free end of the piston (7) during the transition from the connected to the disconnected state.

11. The device according to any of claims 7 to 10, characterized in that the anchor element (11 ) is screwed into the housing (4).6 pages of drawings follow.14

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