Open large image in new tab »
Pic. 23. Front suspension strut: 1. Compression valve body; 2 Compression valve discs; 3. Throttle disc compression valve; 4. Compression valve plate; 5. Compression valve spring; 6 Compression valve clip; 7. Recoil valve nut; 8 Recoil valve spring; 9. Recoil valve plate; 10 Nut washer; 11. Recoil valve disc; 12. Throttle disk of the recoil valve; 13. Piston; 14. Piston ring; 15. Bypass valve plate; 16 Bypass valve spring; 17. Plunger; 18. Plunger spring; 19. Stem guide bushing with PTFE layer; 20. Stem guide sleeve; 21. O-ring of the rack housing; 22. Stem seal; 23. Gland clip; 24. Gasket of a protective ring of a rod; 25. Stem protection ring; 26. Rack housing nut; 27. Compression buffer support; 28. Stock; 29 Suspension spring cup; 30. Stem limit bushing; 31. Rack body; 32. Cylinder; 33. Piston assembly with recoil valve and bypass valve; 34. Compression valve assembly; 35 Swivel arm; I. Scheme of operation of the hydraulic rack; II Compression stroke; III. Recoil move.
The telescopic hydraulic strut is the main front suspension unit. It combines a group of parts, some of which serve as a suspension guide, and others as a damping element. The first group of parts includes the strut body and the details of its fastening to the body and the steering knuckle, the second group includes a hydraulic shock absorber mounted in the strut. The rack body 31 is made of a pipe, the bottom is welded to the lower part, and an internal thread for the nut 26 is cut in the upper part. Outside, the rack body is welded to the bottom - a bracket for connecting to the steering knuckle, in the middle part the support cup 29 of the suspension spring and the swing arm 35 connected to the steering linkage. Two holes are made in the cheeks of the bracket. of which the upper ones are oval for the adjusting bolt. A cylinder 32 is installed in the rack housing, in the lower part of which a compression valve 34 is pressed. Its body is pressed against the bottom of the rack body. The compression valve consists of a body 1, three flat discs 2 and 3, a plate 4, a spring 5 and a clip 6. In the center of the body there is a socket with a chamfer, against which the valve discs and the plate 4 are pressed by the spring 5. The other end of the spring abuts against the clip 6, pressed onto the seat band of the valve body. A cylindrical groove and four vertical grooves are made in the lower part of the housing for the passage of fluid from the rack housing to the cylinder and back. The same grooves are found in the upper part of the compression valve housing. Disks 2 of the compression valve are flat, in the center they have holes for the passage of fluid. In the central hole of the disk 3 there are three cutouts for throttling the liquid at a low speed of the rod. This disk is called the throttle. The plate 4 in the lower central part has a cylindrical protrusion that overlaps the central hole of the disks 2 and 3, but does not cover the throttle cutouts. In the assembled valve between the plate 4 and the disk 3 a gap is formed for the passage of liquid. For this purpose, eight through holes are made in the plate. The clip has a flanging and a cylindrical belt on which the cylinder is mounted. This ensures the tightness between the compression valve and the cylinder 32. On the stamped surface of the cage there are six side and one central holes for the passage of fluid.
The cylinder has a rod 28 assembled with a piston 33, on which a bypass valve and a recoil valve are mounted. The piston has twelve vertical valves arranged along two radii. Four channels, located along a large radius, are closed by a plate 15 of the bypass valve, pressed against the channels by a spring 16. The remaining valves are blocked from below by a package of two recoil valve discs. The upper disk 12 is throttle, has three cutouts along the outer diameter. The next disc 11 is flat. Both disks are pressed against the piston 13 by a spring 8 through the support plate 9. The piston assembly with valves is attached to the stem with a nut 7, which is countered by punching the stem in two places. To protect the recoil valve disks from damage during installation and stabilize the valve operation, a washer 10 is installed between the disks and the nut. The piston is sealed in the cylinder with a ring made of filled fluoroplastic, due to which the wear resistance of the pair increases sharply; cylinder is a piston. A restrictive sleeve 30 is pressed on the rod and then welded, which, resting against the plunger 17 of the hydraulic recoil buffer, limits the recoil stroke.
The hydraulic recoil buffer consists of a plunger 17 and a spring 18, under the action of which the plunger is lowered until it stops against the protrusion of the cylinder. There is a gap between the stem and the plunger through which the cavities above and below the plunger communicate. Between the upper part of the plunger and the cylinder there is a calibrated gap for throttling the fluid, when the sleeve 30 closes the gap between the stem and the plunger from the end. Between the rest of the plunger and the cylinder there is a significant gap due to the increase in the diameter of the cylinder in the area of the lower and middle parts of the plunger (at the lower position of the plunger).
The movement of the rod in the cylinder is directed by a split sleeve 19 with a fluoroplastic insert. The sleeve 19 is pressed into the guide yoke 20. A drain tube is installed in the yoke channel, connecting the upper cavity of the yoke with the annular groove of the telescopic rack housing. The liquid that has passed through the gap between the stem and the guide sleeve is drained through this tube so that there is no foaming of the liquid due to contact with air. The cage assembly with the guide sleeve is pressed onto the cylinder by a cylindrical belt. The cage in the rack body is sealed with a rubber ring 21 Following the guide bushing cage in the rack body, a self-clamping gland 22 of the frame type with a cage 23, a gasket 24 and a protective ring 25 of the stem are installed. All parts installed in the rack housing are pressed with nut 26. In this case, the sealing parts select the gaps between the parts, ensuring the tightness of the rack. The stuffing box 22 is reinforced with a metal frame, as a result of which its necessary rigidity is achieved. Inside the stuffing box there are two working edges adjacent to the surface of the rod. The compression of one of the edges is provided by a spring, the other - due to the elasticity of the rubber gland. Therefore, the gland is called self-clamping. It is installed in a metal cage 23. The ceramic-metal ring protects the working surface of the rod from contamination. Support 27 is pressed onto the body of the rack, against which the buffer of the compression stroke abuts during the compression stroke. In the upper part of the rod there is a thread for the nut for fastening the upper support of the rack and turnkey flats are made to keep the rod from turning when the nut is rotated.