Suspension damping cylinder with adjustable pressure for wheel excavator

Abstract

The present application belongs to the field of engineering machinery, and relates to a suspension damping cylinder, comprising a cylinder upper cover, a cylinder barrel and a cylinder lower cover; a gland is arranged below the cylinder upper cover; a butterfly spring is arranged between the gland and the cylinder lower cover; an adjusting nut and an adjusting bolt are arranged on the cylinder upper cover, and are used for adjusting the compression deformation of the butterfly spring; the damping force of the damping cylinder in the working state is controlled by adjusting the compression deformation of the butterfly spring, so that the smoothness and stability of the excavator in different road conditions can be improved.

Description

Technical Field

[0001] This invention belongs to the field of engineering machinery and relates to a suspension damping cylinder with adjustable pressure for wheeled excavators. Background Technology

[0002] The drive system of a wheeled excavator includes a front steering drive axle and a rear rigid drive axle. The rear rigid drive axle is rigidly fixed to the underframe, while the front steering drive axle is fixed to the underframe by a pin. Therefore, the front steering drive axle can rotate around the pin. The underframe has suspension damping cylinders installed on both sides of the front steering drive axle. When the excavator encounters bumpy road conditions during operation, the vibration can be reduced by the buffering of the suspension damping cylinders, improving the smoothness and stability during operation.

[0003] Currently, the suspension damping cylinders in wheeled excavators are single-acting plunger cylinders. The damping pressure of the existing suspension damping cylinders on the front axle of wheeled excavators is not adjustable during operation, and the extension and retraction stroke of the cylinders is not adjustable, meaning the swing angle of the front axle is not adjustable. The smoothness and stability of the excavator during travel when dealing with different road conditions need to be improved. Summary of the Invention

[0004] To address the aforementioned problems, this invention provides a suspension damping cylinder with adjustable pressure for wheeled excavators. By adjusting the compression deformation of the disc spring, the damping force of the damping cylinder during operation can be controlled, thereby improving the smoothness and stability of the excavator under different road conditions.

[0005] The technical solution provided by this invention is as follows:

[0006] An excavator-use suspension damping cylinder with adjustable pressure includes an upper cylinder cover, a cylinder barrel, and a lower cylinder cover. A pressure cap is provided below the upper cylinder cover, and a disc spring is provided between the pressure cap and the lower cylinder cover. An adjusting nut and an adjusting bolt are provided on the upper cylinder cover for adjusting the compression deformation of the disc spring. The damping force of the damping cylinder in the working state is controlled by adjusting the compression deformation of the disc spring.

[0007] Furthermore, a damping cylinder support seat is provided below the suspension damping cylinder to support the suspension damping cylinder; the adjusting nut is connected to the upper part of the cylinder cover by a threaded connection. By tightening the adjusting nut clockwise, the nut contacts the pressure cover, and the disc spring is compressed and deformed. A piston and piston rod are provided below the cylinder. The pre-compression deformation force of the disc spring is transmitted to the piston rod through the piston, and finally acts on the damping cylinder support seat.

[0008] Furthermore, a locking nut II is provided below the adjusting nut. The locking nut II is used to tighten the adjusting nut and prevent it from loosening. When the adjusting nut is screwed in, the compression deformation of the disc spring and the compression force generated by the deformation reach the preset value. When the locking nut II is tightened, it fits against the upper end face of the cylinder cover.

[0009] Furthermore, the cylinder cover is provided with a double-ended stud, and a hexagonal nut is installed on the double-ended stud. The vibration damping cylinder is fixed by tightening the hexagonal nut.

[0010] Furthermore, the adjusting nut is clearance-fitted at the lower part of the cylinder cover and sealed with an O-ring III to prevent hydraulic oil from overflowing from the position where the adjusting nut fits into the shaft hole of the cylinder cover.

[0011] Furthermore, the adjusting bolt is threaded onto the upper part of the adjusting nut; the vertical distance between the lower end face of the adjusting bolt and the upper end face of the piston rod is less than the vertical distance between the upper end face of the piston rod's largest cylinder and the lower end face of the cylinder's lower cover; the adjusting bolt is clearance-fitted onto the lower part of the adjusting nut, and is sealed with an O-ring II to prevent hydraulic oil from overflowing from the mating position of the adjusting bolt and adjusting nut shaft holes.

[0012] Furthermore, the piston divides the cylinder into upper and lower hydraulic chambers, and the piston and cylinder achieve dynamic sealing through a Yx-type sealing ring I and a right-angle slip ring combination sealing ring I on the piston; an O-ring sealing ring I is provided between the piston and the piston rod; and a Yx-type sealing ring II, a right-angle slip ring combination sealing ring II, and a dustproof ring are provided between the piston rod and the lower cover of the cylinder.

[0013] Furthermore, an O-ring IV is provided between the upper cover of the cylinder and the cylinder barrel, and an O-ring V is provided between the lower cover of the cylinder and the cylinder barrel.

[0014] Furthermore, the piston rod and piston are assembled separately. The piston rod is equipped with a hexagonal slotted nut and a cotter pin for axial positioning of the piston on the piston rod. The gland and cylinder are clearance-fitted. The gland is provided with a round hole to keep the pressure of the two corresponding cavities on the upper and lower surfaces of the gland consistent.

[0015] The present invention also provides an excavator including the above-described excavator with a pressure-adjustable suspension damping cylinder.

[0016] Beneficial effects

[0017] This invention controls the damping force of the damping cylinder during operation by adjusting the compression deformation of the disc spring, thereby improving the smoothness and stability of the excavator under different road conditions; it achieves the combined superposition of the disc spring compression deformation pressure and the cylinder oil pressure, outputting greater piston rod pressure under the same oil supply pressure; the stroke of the piston rod moving axially upward can be adjusted by adjusting the position of the adjusting bolt to achieve an adjustable limit protection function. Attached Figure Description

[0018] Figure 1 This is an assembly diagram of the mechanical structure of this patent;

[0019] Figure 2 for Figure 1 Enlarged view of point I in the assembly diagram;

[0020] Figure 3 for Figure 1 Enlarged view of section II in the assembly diagram;

[0021] Figure 4 for Figure 1 Enlarged view of section III in the assembly diagram;

[0022] Figure 5 This is a three-dimensional isometric view of the mechanical structure of the present invention;

[0023] Figure 6 This is a three-dimensional isometric view of the mechanical structure of the present invention.

[0024] 1. Adjusting bolt; 2. Locking nut I; 3. Adjusting nut; 4. Locking nut II; 5. Cylinder top cover; 6. Pressure cap; 7. Cylinder barrel; 8. Butterfly spring; 9. Piston; 10. Hexagonal slotted nut; 11. O-ring I; 12. Cylinder bottom cover; 13. O-ring II; 14. O-ring III; 15. Double-ended stud; 16. Hexagonal nut; 17. Oil port connector; 18. O-ring IV; 19. Cotter pin; 20. Yx type seal I; 21. Right angle slip ring combination seal I; 22. Piston rod; 23. O-ring V; 24. Yx type seal II; 25. Right angle slip ring combination seal II; 26. Vibration damping cylinder support. Detailed Implementation

[0025] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0026] Therefore, the following detailed description of the embodiments of the invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the invention without inventive effort are within the scope of protection of the invention.

[0027] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0028] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product of this invention is in use. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this invention. In addition, the terms "first," "second," etc., are only used to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0029] Furthermore, terms such as "horizontal," "vertical," and "sag" do not imply that components must be absolutely horizontal or suspended, but rather that they can be slightly tilted. For example, "horizontal" simply means that its direction is more horizontal relative to "vertical," and does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0030] In the description of this invention, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set," "install," "connect," and "link" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0031] Example 1

[0032] An excavator suspension damping cylinder with adjustable pressure includes an upper cylinder cover 5, a cylinder barrel 7, a lower cylinder cover 12, a double-ended stud 15, a pressure cap 6, a disc spring 8, a piston 9, a piston rod 22, an adjusting nut 3, and an adjusting bolt 1; the preload of the overall assembly of the damping cylinder is achieved by fastening it with a hexagonal nut 16 installed on the double-ended stud 15;

[0033] The adjusting nut 3 of the damping cylinder is connected to the upper part of the cylinder cover 5 by a threaded connection. By tightening the adjusting nut 3 clockwise, the adjusting nut 3 can be made to contact the pressure cover 6, and the disc spring 8 is compressed and deformed. The compression force of the disc spring 8 is linearly related to the amount of compression deformation. The pre-compression deformation force of the disc spring 8 is transmitted to the piston rod 22 through the piston 9, and finally acts on the damping cylinder support seat 26. The cylinder cover 5 is provided with an oil port connector 17. The adjusting nut 3 is clearance-fitted at the lower part of the cylinder cover 5 and sealed with an O-ring III 14 to prevent hydraulic oil from overflowing from the adjusting nut 3 at the shaft hole fit position of the cylinder cover 5.

[0034] The tightening and anti-loosening of the adjusting nut 3 is achieved by the locking nut II4. When the adjusting nut 3 is screwed into the preset position, that is, when the compression deformation of the disc spring 8 and the compression force generated by the deformation reach the preset value, the locking nut II4 is tightened so that the locking nut II4 is in contact with the upper end face of the cylinder cover 5. A locking nut I2 is provided above the adjusting nut 3. Since the disc spring 8 may generate an upward force when it moves, pushing the adjusting nut 3 upward, the locking nut I2 is used to adjust the relative position of the adjusting bolt 1 and the adjusting nut 3 to prevent the adjusting bolt 1 and the adjusting nut 3 from separating from each other.

[0035] The adjusting bolt 1 is connected to the upper part of the adjusting nut 3 by a threaded connection. The adjusting nut 3 is fixed in place, and the adjusting bolt 1 is screwed in clockwise until its lower end face contacts the upper end face of the piston rod 22. Then, the adjusting bolt 1 is screwed out counterclockwise. The distance the adjusting bolt 1 is screwed out counterclockwise is the maximum upward stroke of the piston rod when oil enters the lower oil port of the cylinder. When adjusting the maximum upward stroke of the piston rod, ensure that the vertical distance between the lower end face of the adjusting bolt 1 and the upper end face of the piston rod 22 is less than the vertical distance between the upper end face of the largest cylindrical part of the piston rod 22 and the lower end face of the lower cover 12 of the cylinder (i.e.,...). Figure 4 The distance L in the enlarged view at point III ensures that when the piston rod 22 moves upward to its maximum limit, the piston rod 22 will not contact the lower cover 12 of the cylinder, thus realizing the over-limit protection function of the piston 9 and the piston rod 22 stroke; the adjusting bolt 1 is a clearance fit at the lower part of the adjusting nut 3 and is a static seal. This position is sealed with an O-ring II13 to prevent hydraulic oil from overflowing from the mating position of the adjusting bolt 1 and the adjusting nut 3 shaft hole;

[0036] Piston 9 divides cylinder 7 into upper and lower hydraulic chambers. The piston 9 provides dynamic sealing in the upper and lower hydraulic chambers of cylinder 7. This sealing is achieved by Yx-type sealing ring I20 and right-angle slip ring combination sealing ring I21 on piston 9. The sealing between cylinder upper cover 5, cylinder lower cover 12 and cylinder 7 is static sealing, achieved by O-ring sealing ring IV18 and O-ring sealing ring V23.

[0037] The axial position of piston 9 on piston rod 22 is achieved by the hexagonal slotted nut 10 and cotter pin 19 installed on piston rod 22, as well as the shoulder of piston rod 22. When oil enters the lower oil chamber of the cylinder, the pressure in the lower oil chamber is greater than the pressure in the upper oil chamber, and piston 9 drives piston rod 22 to move upward together. The seal between piston 9 and piston rod 22 is a static seal, achieved by O-ring seal I11. The seal between piston rod 22 and lower cover 12 of cylinder is a dynamic seal, achieved by Yx-type seal II24, right-angle slip ring combination seal II25, and dustproof ring 26.

[0038] The pressure cap 6 and cylinder 7 are clearance-fitted, and no sealing structure is used between them. Therefore, the pressure in the two cavities corresponding to the upper and lower surfaces of the pressure cap 6 is the same. When the damping cylinder is working, the oil pressure at the upper and lower oil ports drives the piston 9 to move up and down. The function of the pressure cap 6 is not only to bear the pressure applied to the disc spring 8 by the adjusting nut 3, but also to constrain the inner ring of the disc spring 8, preventing the disc spring 8 from shifting in the circumferential direction during operation. (The piston 9 constrains the outer ring of the disc spring 8, ensuring that all disc springs do not shift in the circumferential direction.) Given the above-mentioned bearing and constraint guiding functions of the pressure cap 6, the gap between the pressure cap 6 and the cylinder 7 is small. Otherwise, the pressure cap 6 would flip over when bearing the load in the cylinder 7, resulting in a jamming phenomenon. Adding a round hole to the pressure cap 6 can increase the cross-sectional area for oil passage, ensuring that the pressure in the two cavities corresponding to the upper and lower surfaces of the pressure cap 6 remains consistent during the up and down movement of the cylinder, especially at high speeds.

[0039] The piston rod 22 and piston 9 are assembled separately, and the connection between the piston rod 22 and piston 9 is fastened by a hexagonal slotted nut 10 and a cotter pin 19. The separate assembly of the piston rod 22 and piston 9 makes disassembly easier. The piston rod 22 has a smaller diameter, a larger extension length, and directly bears the external load, and is made of a material with better mechanical properties (e.g., 45 steel + forging + heat treatment). The assembly contact position of the piston rod 22 and piston 9 is a small clearance fit suitable for the O-ring seal I11, which can effectively reduce the stress level at this position when the piston rod 22 is subjected to impact loads. In the event of fatigue failure, the separate assembly is more economical.

[0040] The piston 9 reciprocates rapidly within the cylinder 7, which is made of No. 20 steel. The piston 9 can be made of gray cast iron (HT250 + heat treatment). The surfaces of the piston 9 and the piston rod 22 are fitted with steel and cast iron, which improves the wear resistance of both.

[0041] This invention controls the amount of compression deformation of the disc spring by adjusting the relative position of the adjusting nut on the cylinder cover, thereby adjusting the damping force of the damping cylinder in a flexible working state. The combined effect of the adjusting nut's compression deformation force on the disc spring and the cylinder oil pressure can output a larger piston rod pressure. The piston's axial upward movement stroke can also be adjusted by adjusting the position of the adjusting bolt to achieve the function of adjustable limit protection for the piston rod, which is the adjustable limit protection function for the swing angle of the front axle.

[0042] Example 2

[0043] An excavator includes the suspension damping cylinder described in Example 1.

[0044] The embodiments of the present invention have been described above with reference to the accompanying drawings. However, the present invention is not limited to the specific embodiments described above. The specific embodiments described above are merely illustrative and not restrictive. Those skilled in the art can make many other forms under the guidance of the present invention without departing from the spirit and scope of the claims. All of these forms are within the protection scope of the present invention.

Claims

1. A suspension damping cylinder, characterized in that, The system includes a cylinder barrel, an upper cylinder cover, and a lower cylinder cover. The upper and lower cylinder covers are respectively located above and below the cylinder barrel. A pressure cap is located below the upper cylinder cover, and a butterfly spring is located between the pressure cap and the lower cylinder cover. An adjusting nut and an adjusting bolt are located on the upper cylinder cover. The adjusting nut and adjusting bolt cooperate to adjust the compression deformation of the butterfly spring. The damping force of the damping cylinder in operation is controlled by adjusting the compression deformation of the butterfly spring. A locking nut II is located below the adjusting nut. The locking nut II is used to tighten the adjusting nut and prevent loosening. When the adjusting nut is screwed in, the compression deformation of the butterfly spring and the compression force generated by the deformation reach a preset value. When the locking nut II is tightened, it fits against the upper end face of the upper cylinder cover. A locking nut I is located above the adjusting nut. The locking nut I is used to adjust the relative position of the adjusting bolt and the adjusting nut to prevent them from separating.

2. The suspension damping cylinder according to claim 1, characterized in that, A damping cylinder support seat is provided below the suspension damping cylinder to support the suspension damping cylinder; the adjusting nut is connected to the upper part of the cylinder cover by a threaded connection. By setting the position of the adjusting nut, the nut contacts the pressure cover, and the disc spring is compressed and deformed by force. A piston and piston rod are provided below the cylinder. The pre-compression deformation force of the disc spring is transmitted to the piston rod through the piston and finally acts on the damping cylinder support seat.

3. The suspension damping cylinder according to claim 1, characterized in that, The cylinder cover is provided with a double-ended stud, and a fastening nut is installed on the double-ended stud to fix the vibration damping cylinder.

4. The suspension damping cylinder according to claim 1, characterized in that, The adjusting nut and the lower part of the cylinder cover are in a clearance fit relationship and are sealed with the first sealing ring III to prevent hydraulic oil from overflowing from the adjusting nut at the shaft hole of the cylinder cover.

5. The suspension damping cylinder according to claim 2, characterized in that, The adjusting bolt is threaded on the upper part of the adjusting nut; the vertical distance between the lower end face of the adjusting bolt and the upper end face of the piston rod is less than the vertical distance between the upper end face of the piston rod and the lower end face of the cylinder cover; the lower part of the adjusting bolt and the adjusting nut are in clearance fit, and the first sealing ring II is used for sealing to prevent hydraulic oil from overflowing from the mating position of the adjusting bolt and the adjusting nut shaft hole.

6. The suspension damping cylinder according to claim 2, characterized in that, The piston separates the cylinder into upper and lower hydraulic chambers. The piston and cylinder are dynamically sealed by the second sealing ring I and the third sealing ring I on the piston. A first sealing ring I is provided between the piston and the piston rod. A second sealing ring II, a third sealing ring II, and a dustproof ring are provided between the piston rod and the lower cover of the cylinder.

7. The suspension damping cylinder according to claim 1, characterized in that, A first sealing ring IV is provided between the upper cover of the oil cylinder and the cylinder barrel, and a first sealing ring V is provided between the lower cover of the oil cylinder and the cylinder barrel.

8. The suspension damping cylinder according to claim 2, characterized in that, The piston rod and piston are assembled separately. The piston rod is equipped with a slotted nut and a cotter pin for axial positioning of the piston. The gland and cylinder are clearance-fitted. The gland is provided with a round hole to keep the pressure of the two corresponding cavities on the upper and lower surfaces of the gland consistent.

9. An excavator, characterized in that, Includes the suspension damping cylinder as described in any one of claims 1 to 8.

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