RU2065543C1 - Drive for rod of pressing mechanism - Google Patents

Abstract

FIELD: mechanical engineering. SUBSTANCE: plunger 4 interacts with spherical tip 9 of lever 1. Spherical hollow 11 is made on the end face of the plunger. The center of the hollow is on the axis of plunger 9. The hollow serves for interaction with the spherical tip of one of the arms of lever 1. EFFECT: improved design. 1 dwg

Description

 The invention relates to the field of drives in which a reduction in the travel of the driven element is required compared with the lead, in particular, to a control system for reversing the thrust of a turbojet engine.

 Known actuator rod of the pressure mechanism, containing a rotary two-arm lever, one of the shoulders of which has a spherical tip, a housing mounted in it with the possibility of reciprocating movement of the pusher, one end of which is designed to interact with the rod of the pressure mechanism 1.

 The specified drive is designed to ensure the operation of the lock switch when moving the piston of the lock spool up.

 The disadvantage of this rod drive is that during large operating times (starting from 12,000 hours), wear products and fretting corrosion are formed inside the plunger from its interaction with the rod at the place of their contact.

 When the thrust reverse is turned on, the rod, when moving quickly relative to the pusher (in 0.3 seconds) through the hole in the pusher, carries out (throws) products (particles) of wear and corrosion from the inside of the pusher, which then fall back into the gap between the housing bushing and the pusher the pusher, as a result of which, when the thrust reverser is subsequently turned on, the particles that get into the gap create a wedging of the pusher, which leads to an increase in the resistance force when moving the lock piston piston that exceeds the specified value for those conditions. An increase in the indicated resistance force is also promoted by an increase in the friction force when the rod moves inside the pusher due to the presence of products of their wear. The developed force from the air pressure under the piston of the lock spool becomes insufficient to overcome the increased resistance force, as a result of which the openings in its sleeve are not opened by the piston and the compressed air does not enter the power pistons of the main cylinders, which leads to non-relocation of the thrust reversal flaps and, as a result , to the premises for the accident (PAP).

 The technical result of the invention is to increase the reliability of the actuator rod of the pressure mechanism by simplifying the design of its pusher.

 The solution to this problem is achieved by the fact that in the rod actuator of the pressure mechanism containing a pivot arm, one of the shoulders of which has a spherical tip, a housing mounted in it with the possibility of reciprocating movement of the pusher, one end of which is designed to interact with the rod of the pressure mechanism, at the end a pusher intended to interact with a spherical tip, made a spherical recess with a center lying on the axis of the pusher, and designed to interact with the spherical The eric tip of one of the lever arms.

 The drawing shows the actuator rod of the pressure mechanism.

 The drive consists of a two-shouldered lever 1 mounted in the housing 2, with the possibility of rotation around the axis 3, the pusher 4, the return spring 5 and the rod 6 of the push mechanism (switch) 7. One arm of the lever 1 is in contact with the driving element of the piston 8 of the lock spool, the second shoulder contains a spherical tip 9, interacting with the end face of the pusher 4. The pusher 4, made in the form of an integral part, is installed in the housing (along the sleeve) with contact along a cylindrical surface with the possibility of reciprocating movement along the axis. At the end of the pusher intended for interaction with the spherical tip of the lever, a spherical recess 11 is made with a center lying on the axis of the pusher.

 The second end of the pusher 4 interacts with the rod 6 of the pressure mechanism 7.

 The pusher 4 has a shoulder for installing a cylindrical compression spring 5, the second end of which abuts against the housing. The spring 5 constantly pushes the pusher 4 to the spherical tip 9 of the lever 1, ensuring constant contact of the other shoulder of the lever with the end face of the piston 8.

 The operation of the switch 7, at a certain position of the piston 8 relative to the holes 12 of the sleeve 13, is provided by the selection of the thickness of the adjusting washers 14 and 15.

 The drive operates as follows.

 In the drawing, the drive is shown in the position corresponding to the engine operating mode on “direct thrust” (thrust reverse is turned off). In this position, the piston 8 under the action of its return spring occupies the lowest position. Under the action of the return spring 5, the pusher 4 occupies a lower position, ensuring the interaction of the end of the pusher with a spherical tip 9 and the other shoulder of the lever 1 with the end face of the piston 8.

 When the thrust reverse is turned on under the action of compressed air supplied under the piston 8, the latter begins to move up and through the lever 1 moves the pusher 4 and the stem 6 of the switch 7 to the left, compressing the return spring 5.

 At the beginning of the movement, the spherical tip 9 slides along the plane 10 toward the axis of the pusher, triggering the switch 7, then moving on to the spherical recess 11.

 With further movement, the piston 8 opens the holes 12 in the sleeve and the compressed air enters through the holes 12 to the power pistons that move the reverse flaps to the “reverse thrust”. When the thrust reverse is turned off, the cavity under the piston 8 communicates with the atmosphere, as a result of which the piston moves back down under the action of the piston return spring.

 Under the action of the spring 5, the pusher 4 moves to the right to its original position, while the spherical tip 9 passes from the spherical recess 11 to the plane 10. At the same time, the rod 6 of the switch 7 is released from the action of the pusher 4. The switch 7 returns to its original position.

 There are no mutually moving parts and a spacer spring in the actuator rod drive, which eliminates the appearance of wear products and fretting corrosion, which fell into the gap between the pusher and the sleeve of the housing and led to jamming of the pusher and to the exclusion of reverse thrust. By canceling the internal spacer spring of the pusher, the resistance force when the piston 8 moves to open the holes 12 in the sleeve 13 when the thrust reverse is turned on decreases by 20%, which is equivalent to an increase in the air pressure reserve under the piston 8 for its reliable operation.

 Due to the execution at the end of the pusher 4 of the spherical recess 11, its full stroke is less than the stroke of the spherical tip (along the axis of the pusher) and is 5.5 mm and does not exceed the required stroke of the switch rod 7.

 In addition, in connection with the elimination of the source of the appearance of wear and corrosion products, it is possible to increase the frequency of preventive washing of the pusher in operation.

Claims (1)

 The actuator of the rod of the push mechanism, comprising a rotary two-arm lever, one of the shoulders of which has a spherical tip, a housing mounted therein with the possibility of reciprocating movement of the pusher, one end of which is designed to interact with the rod of the push mechanism, characterized in that at the end of the pusher, designed to interact with a spherical tip, made a spherical recess with a center lying on the axis of the pusher, designed to interact with a spherical tip m of one of the shoulders of the lever.