RU2334135C1 - Aircraft airframe compartment threaded joint - Google Patents

Abstract

FIELD: transport.

SUBSTANCE: aircraft airframe compartment threaded joint comprises an inner thread compartment and an annular groove compartment, the annular groove housing a threaded split ring with a spacer ring arranged thereon, the said threaded and space rings being furnished with aligned radial through holes. The joint incorporates also a thin-wall split-washer arranged between the aforesaid rings end face planes and the annular groove end face on the side opposite to the inner thread compartment, the said split-washer being furnished with a central flanging located in counterpart annular groove made in the threaded split ring. The end faces of the annular groove and threaded split rind in contact with the thin-wall split-washer are furnished with radial recesses housing the thin-wall split-washer central and outer-edge flanges pressed therein.

EFFECT: higher reliability of the aforesaid joint.

4 dwg

Description

The present invention relates to the field of rocketry and can be used in the construction of detachable joints in the hulls of aircraft compartments (LA) - missiles, shells, as well as in mechanical engineering.

A known design is the threaded connection of the housing compartments, in which an internal thread is cut at the end of one compartment, and an external thread is cut at the end of the other compartment, and the connection is screwed on one end of the compartment to the other until they become mutually angular with the lock nut [I.S. Golubev, A.V. Samarin. "Design of aircraft structures." - M .: Engineering, 1991, p. 236, Fig. 5.28 “b”].

The disadvantages of this design are:

1) The impossibility of ensuring the required accuracy in the skew axis of the compartments due to the lack of an end drive belt, since a lock nut is used as an end stop, which leads to aerodynamic asymmetry of the airframe of the aircraft and an increase in the eccentricity of the aircraft engine thrust;

2) The presence of a gap on the outer surface of the aircraft at the junction of the compartments with a width greater than the thread pitch, which reduces the rigidity of the structure, and on hypersonic aircraft leads to heating of the case;

3) Connection of the compartments by their relative mutual rotation, which makes it impossible to install electrical and other communications in the aircraft body that require relative angular orientation of the compartments during assembly.

These disadvantages are eliminated in the design of the threaded connection of the aircraft body compartments selected by the prototype of the present invention, comprising one compartment with an internal thread and a second compartment, which is provided with an annular groove with a split threaded ring located therein, made with an external thread interacting with the internal thread of the first compartment, and equipped with a cylindrical girdle telescopically covered by a spacer ring, while on the outer surface of the spacer ring through radial holes are made I, combined with similar holes in the cylindrical collar of the split ring [RF patent №2268405 dated 20.04.2004, IPC ⁷ F16V 7/00, F16B 17/00, F42B 15/36, B64G 1/64]. When assembling the aircraft body, a pin spanner pin is installed in the holes and the joint is tightened until the abutted parts stop against the ends of the spacer ring.

The design of the prototype ensured accuracy in the skew axis of the aircraft compartments, oriented relative to each other in a given position of the aircraft compartment, and the absence of a gap on the outer surface of the aircraft at the junction of the compartments.

The disadvantage of the described device, however, is the lack of reliability due to the possibility of unscrewing the threads, especially in missiles that experience high-intensity vibration loads in flight, the reason for which is the lack of locking of the threaded connection;

The usual methods of preventing the unscrewing of the thread by mechanical locking of the threaded connection, used in mechanical engineering (for example, using locking screws, punching, adhesives, etc.), are not suitable for such a connection, since the use of locking screws requires a sufficient thickness of the compartment body, which is performed in missiles, usually thin-walled, punching leads to partial destruction of the threaded joint during possible disassembly of the assembly, and the use of adhesives, primers, sealants, etc. - uncontrolled and, accordingly, unreliable.

In aircraft engine building, locking of threaded fasteners with washers from sheet steel is widely used [Yu.M. Nikitin. "Design of parts and components of aircraft engines." - M .: Mechanical Engineering, 1968, p.207 ... 225], the variants of which, the most possible for the proposed connection, may be:

- locking with washers with a folding antennae [p. 214, fig. 6.36; p. 220, Fig. 6.48; p.221, fig.6.49];

- locking with a folding cup [p. 218, Fig. 6.44].

However, these locking options are unacceptable for the proposed connection, because:

- locking with washers with a folding antennae requires ensuring mutual angular orientation of the grooves for the antennae on the joint nut and the body part, which is impossible with tight tightening of the joint;

- locking the folding cup associated with the coverage of one of the parts on the outer surface, which is also unacceptable.

The task of the invention is to increase the reliability of the threaded connection of the aircraft body compartments by ensuring its mechanical locking after screwing.

The solution to this problem lies in the fact that in the threaded connection of the aircraft body compartments, containing one compartment with an internal thread, a second compartment with an annular groove, a threaded split ring, a spacer ring mounted on it and through radial holes combined with each other, made in the threaded and spacer rings, a thin-walled split washer is inserted, located between the plane of the ends of the split threaded and spacer rings and the end of the annular groove from the side opposite to the compartment with morning thread and equipped with a central flange located in the reciprocal annular groove made in a split threaded ring, while the ends of the annular groove and the split threaded ring in contact with the thin-walled split washer are provided with radial recesses in which sections of the outer contour and the central flange of the thin-walled split washer are stamped .

The introduction of a thin-walled split washer located between the plane of the ends of the split threaded and spacer rings and the end of the annular groove from the side opposite to the compartment with the internal thread ensured that the locking device was implemented in the dimensions of the threaded joint of the compartments.

The execution of the washer with a central flange located in the reciprocal annular groove made in a split threaded ring, excludes the possibility of the outer contour of the washer beyond the caliber of the aircraft when making up.

The execution of the ends of the annular groove in contact with the thin-walled split washer and the split threaded ring with radial recesses, into which the sections of the outer contour and flanging of the split thin-walled washer are stamped, provides mechanical locking of the threaded connection after screwing the compartments.

The invention is illustrated by drawings, which show:

figure 1 is a longitudinal section in place of the docking holes;

figure 2 is a longitudinal section in place of the radial grooves;

figure 3 is a view of the outer radial recesses;

figure 4 is a transverse section in place of the radial recesses.

The proposed threaded connection of the aircraft body compartments contains one compartment 1 (Fig. 1) with an internal thread and a second compartment 2 provided with an annular groove 3 with a split threaded ring 4 located therein, made with an external thread 5, interacting with the internal thread of the first compartment 1, and equipped with a cylindrical belt 6, telescopically covered by a spacer ring 7, while on the outer surface of the spacer ring there are made radial holes 8, combined with similar holes 9 in a cylindrical belt section th ring.

In the annular groove 3 between the plane 10 formed by the ends of the spacer ring 7 and the split ring 4 and the rear end 11 of the annular groove, a thin-walled split washer 12 is installed, provided with a central flange 13 located in the mating annular groove 14 of the split ring 4.

At the rear end of the annular groove 3, radial recesses 15 are made (Fig. 2), and at the rear end of the split ring 4 there are recesses (grooves) 16 into which the flanging sections 17 of the thin-walled washer 12 are stamped.

The operation of the device is as follows.

When connecting the compartments 1 and 2 of the aircraft body, their mechanical docking includes:

- installation in an annular groove 3 of a sequentially split washer 12, a split ring 4 to ensure that the punchings 17 of the washer 12 enter the grooves 16, and the spacer ring 7;

- preliminary mutual angular orientation of the compartments;

- screwing the compartments to the stop by joint rotation of the split ring 4 and the spacer ring 7 using a wrench with a pin in the holes 8 and 9. In this case, the thin-walled washer 12 rotates together with the split ring 4 due to the interaction of the side walls of the grooves 16 of the ring 4 with stampings 17;

- locking the threaded connection by stamping sections 18 of the outer contour of the washer 12 using a special impact tool 19, which eliminates the possibility of loosening the tightening or unscrewing of the threaded connection.

Thus, the proposed device provides improved reliability of the threaded connection of the aircraft body compartments by providing mechanical locking of the connection after screwing the compartments.

Claims (1)

A threaded connection of the aircraft body compartments, comprising one compartment with an internal thread and a second compartment with an annular groove, in which a threaded split ring is placed, a spacer ring mounted on it and through radial holes combined in each other in the threaded and spacer rings, characterized in that a thin-walled split washer inserted between the plane of the ends of the split threaded and spacer rings and the end of the annular groove from the side opposite to the compartment with the internal thread d, and equipped with a central flange located in the reciprocal annular groove made in a split threaded ring, while the ends of the annular groove and the split threaded ring in contact with the thin-walled split washer are provided with radial recesses into which sections of the outer contour and the central flange of the thin-walled split washer are stamped .

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