JPH0650084B2 - Rocket thrust canceller - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to a thrust canceling device for a rocket, and more specifically, abnormal combustion occurs in the propellant during the flight of the rocket, or the orbit is greatly deviated. The present invention relates to a device for canceling thrust generated by a rocket nozzle by opening a window on a front end plate of a rocket motor in an emergency where the flight of the rocket poses a danger.

[Prior Art] FIG. 3 illustrates a rocket having a conventional thrust canceling device.

In the figure, 1 is a rocket motor constituting the rocket, and 1'is the motor 1 connected to the rocket motor.
It is the upper stage rocket motor.

In the rocket motor 1, 2 is a motor case, 3 and 4 are front and rear end plates of the motor case, 5 is a propellant loaded in the motor case 2, 6 is a rocket nozzle fastened to the rear end plate 4, and 7 is An igniter attached to the front end plate 3 and a connecting cylinder 8 for connecting the upper stage rocket motor 1 '.

In the above standard rocket motor, the thrust canceller is configured as follows.

11 is a circular transparent window opened in the central portion of the front end plate 3, 12
Is a cover plate of this transparent window, and the cover plate 12 is formed integrally with the igniter 7 and is fastened to the front end plate 3 by a plurality of explosive-operated separation nuts 13. When the rocket nozzle 6 ejects the rocket nozzle 6 and the above-mentioned emergency occurs, a command to open the rocket issues a window opening command, and the plurality of separation nuts 13 respond to this command. To divide. As a result, the fastening of the lid plate 12 is released, so that the lid plate is discharged into the connecting cylinder 8 together with the igniter 7, and the transparent window 11 is opened. Therefore, the combustion gas of the propellant 5 is ejected from this opening, and the thrust generated in the rocket nozzle 6 is canceled by the reaction force thereof.

From the above, the ejection amount of the combustion gas, that is, the opening area of the transparent window 11 is determined so that the reaction force becomes substantially equal to the thrust force. That is, A≈At · K (1) where A is the opening area of the transparent window 11, At is the cross-sectional area of the throat 6a of the rocket nozzle, and K is the thrust coefficient of the rocket nozzle 6. The thrust coefficient is a constant determined by the following equation.

T = Tt + Ts = K · Tt (2) where T is the total thrust generated by the rocket nozzle 6, Tt is the thrust generated by the throat 6a, and Ts is the thrust generated by the skirt 6b of the nozzle. , The thrust component Ts is the thrust axial component force P of the jet gas pressure P exerted on the skirt portion 6b.
It is a value obtained by integrating 1 over the entire skirt portion.

In some cases, the igniter portion shown in FIG. 1 of JP-A-58-85346 may be provided with a cover plate similar to the one described above.

〔problem〕

By the way, when such a thrust canceling device is adopted, it is difficult to standardize the motor case, in particular, the front end plate of the motor case, which causes a problem of high cost. The reason will be described below.

Generally, in a practical large-sized rocket motor, the diameter of the motor case and the shape of the end plate immediately afterward are standardized, and the type, shape, and amount of the propellant are selected based on the thrust specifications required for the rocket motor. The specifications such as the throat area of the rocket nozzle and the skirt shape are set according to. Here, even if the total length of the motor case may change depending on the specifications, it is extremely easy to change it.Also, even if the above specifications of the rocket nozzle are changed, the shapes of the fastening parts are made uniform so that the rear end plate is Standardization is possible. However, when the through window for thrust canceling is opened in the front end plate, the opening area must be set according to the thrust performance as described above, which causes a decrease in strength and an increase in weight of the end plate. It is very difficult to standardize it without it. Therefore, the design of the front end plate needs to be changed every time the thrust specification changes, and the production equipment and tools must be updated accordingly, resulting in higher costs.

Therefore, an object of the present invention is to form a transparent window having an arbitrary desired area without changing the basic design of the front end plate.

[Means for Invention]

The means of the present invention for solving the above-mentioned problems is to set a virtual fenestration contour line on the front end plate, and dispose a V-shaped molded explosive wire so as to face the fenestration contour line.

[Action]

The V-shaped molded explosive wire is a groove-shaped charge holder in which an explosive charge is pressed and a V-shaped groove is further formed on the exposed surface of the charge. When the charge is detonated in a state where they are opposed to each other at a distance (standoff), the steel sheet is instantaneously melted along the extending direction of the V groove by a so-called Neumann action.

Therefore, according to the above-mentioned means, since the inclusion area of the virtual fenestration contour line set on the front end plate can be freely selected, the above-mentioned V-shaped explosive wire of the V-shaped explosive wire arranged so as to face the contour line can be freely selected. Due to the fusing action, it is possible to instantly form the transparent window having the desired opening area as described above in response to the window opening command.

〔Example〕

In FIGS. 1 and 2, reference numeral 15 denotes a front end plate of a rocket motor, which has the same basic structure as that of the reference numeral 1 shown in FIG. Reference numeral 16 is a boss for mounting an igniter formed in the central portion of the front end plate 15, 17 is a boss hole for this boss, 18 is the igniter, 18a is a mounting flange for the igniter, and 20 is an annular center holder for ignition. The base of the container 18 is fitted into the boss hole 17, and the flange 18a
The center holder 20 is arranged in front of the above, and these are fastened together with the front surface of the boss 16 by a plurality of bolts 21.

Reference symbol S is a contour line of the transparent window to be opened in the front end plate 15, and this fenestration contour line S is substantially circular with a diameter D. The diameter D is determined based on the equation (1).

22 is a V-shaped molded explosive wire (hereinafter referred to as explosive wire),
As described above, it comprises the groove-shaped charge holder 23 and the explosive charge 25 in which the V-shaped groove 24 is formed by being pressed into the charge holder. Further, the explosive wire 22 is made as a whole in a C-shaped annular shape having the diameter D as a central diameter, and both ends thereof are gently drawn inward so that their ends are coaxially opposed to each other. A detonation block 26 for detonating an explosive charge 25 is provided.

Reference numeral 27 denotes six retainers, which are radially arranged with one end fixed to the center holder 20. Then, the explosive wire 22 is fixed to the outer ends of these retainers, and is made to face the fenestration contour line S with the standoff 1 interposed therebetween.

A safety device 28 is provided with a safe arm mechanism and is fixed to the center holder 20. 29 and 29 are a pair of sharp detonators attached to this safety device, and 30 and 30 are a pair of sealed detonators, one end of each detonator 30 is inserted into the safety device 28, and The detonator tubes 29 on one side are opposed to each other via a safe arm mechanism, and the other ends are connected to the detonation block 26. The safe arm mechanism switches to the arm position before launching the rocket to form a flame path from the detonator 29 to the detonator 30. Further, the system including the detonator tube 29 and the detonating wire 30 is configured by two systems as described above, in order to add redundancy and improve reliability.

Reference numeral 31 is a core detonator, which transmits the window opening command from the command to each detonator 29.

The embodiment is as described above. When the fenestration command is transmitted to the detonators 29, 29 via the basic detonating wire 31, these detonating tubes detonate and the detonation wave causes the detonating wire 30. , 30 to reach the detonation block 26 and excite it. Therefore, the explosive charge 25 of the explosive wire 22 is point-exploded and melts the front end plate 15 in the extending direction of the V groove 24. That is, the contour line S
A transparent window with the desired opening area is instantly opened along.

〔effect〕

As described above, according to the present invention, in opening the front end plate in an emergency, it is possible to open any desired transparent window regardless of the shape of the end plate, thereby standardizing the motor case. Can be further promoted, which leads to cost reduction.

In addition to the above effects, the present invention can open a window by detonating one V-shaped molded explosive wire, so that the number of detonation points is significantly reduced as compared with the case where a plurality of separation nuts and the like are conventionally used. Therefore, there is an advantage that the reliability can be greatly improved.

[Brief description of drawings]

FIG. 1 is an end view of a rocket motor embodying an example of the present invention, FIG. 2 is a sectional view taken along the line II-II of FIG. 1, and FIG. 3 is a longitudinal sectional view of a main part of a rocket equipped with a conventional device. is there. 1 ... Rocket motor 3 ... Front end plate 6 ... Rocket nozzle 11 ... Through window 15 ... Front end plate 22 ... V-shaped molded explosive wire S ... Open window contour line

Claims (1)

[Claims] 1. A device for canceling thrust generated by a rocket nozzle by opening a front end plate of a rocket motor in an emergency, wherein a virtual fenestration contour line is set on the front end plate, A thrust canceling device for a rocket that has a V-shaped molded explosive wire arranged facing the contour line.