Damper with axial flow channel for position-sensitive characteristics

Abstract

The present invention discloses a damper having an axial flow channel that can realize position-sensitive characteristics, a damper outer tube, and a piston assembly slidably connected to the damper outer tube. The inner cavity of the damper outer tube is divided into an upper chamber and a lower chamber by the piston assembly. A piston rod is provided on one side of the piston assembly located in the upper chamber. The end of the piston rod away from the piston assembly passes through the damper outer tube and is located on the outside of the damper outer tube. An axial flow channel tube is also provided between the damper outer tube and the piston assembly. The axial flow channel tube has a plurality of evenly distributed axial flow channels, and the width of the axial flow channels varies at different positions. The damping coefficient of the damper of the present invention can change in real time with the position of the piston relative to the damper tube, thereby realizing the displacement sensitivity of the single-rod structure damper and ensuring that the piston does not deviate radially.

Description

Technical Field

[0001] The present invention relates to the technical field of shock absorption, and in particular to a damper with an axial flow channel capable of realizing position-sensitive characteristics. Background Art

[0002] As demand for ride comfort continues to rise, variable damping coefficient dampers are increasingly used in automotive suspensions. Magnetorheological dampers, which adjust the damping coefficient by adjusting magnetic field intensity, and CDC dampers, which adjust the damping coefficient by adjusting the flow channel size, are the most commonly used. However, due to the delay of tens to hundreds of milliseconds in adjusting the damping coefficient, these dampers are less effective in suppressing high-frequency vibrations, especially shocks.

[0003] The damping coefficient of a displacement-sensitive damper is dependent on the relative position of the piston and the damper's outer cylinder and can change with changes in the piston's position. Because the damping coefficient of a displacement-sensitive damper does not require current to adjust, there is no response delay associated with current or magnetic fields. This allows for zero-delay adjustment, significantly reducing high-frequency vibration and shock.

[0004] However, the damping gap of traditional displacement-sensitive dampers is the annular gap between the piston and the damper outer cylinder. This requires a dual-rod design to prevent radial piston displacement. However, compared to single-rod dampers, dual-rod designs have shorter strokes and limited application scenarios. Furthermore, the variable inner diameter cylinder and dual-rod design require extremely high machining precision, making it difficult to popularize. Summary of the Invention

[0005] Based on the technical problems existing in the background technology, the present invention proposes a damper with an axial flow channel that can achieve position-sensitive characteristics. The damping coefficient of the damper can change in real time with the position of the piston relative to the damper cylinder, realizing the displacement sensitivity of the single-rod structure damper and ensuring that the piston does not shift radially.

[0006] The damper with an axial flow channel that can realize position-sensitive characteristics proposed in the present invention includes a damper outer tube, a piston assembly is slidably connected to the damper outer tube, and the inner cavity of the damper outer tube is divided into an upper chamber and a lower chamber by the piston assembly. The piston assembly is provided with a piston rod on one side of the upper chamber, and the end of the piston rod away from the piston assembly passes through the damper outer tube and is located on the outside of the damper outer tube. An axial flow channel tube is also provided between the damper outer tube and the piston assembly, and the axial flow channel tube is provided with a number of evenly distributed axial flow channels, and the width of the axial flow channels is different at different positions.

[0007] Preferably, the width of the axial flow channel decreases from the middle to both ends.

[0008] Preferably, the piston assembly includes a piston core, a groove for installing an excitation coil extending inward from the outer circumference of the piston core, and a piston core end cover is provided on one side of the piston core located in the lower chamber, and the piston core end cover is connected to the piston core by fasteners.

[0009] Preferably, a coil sealing ring is sleeved on the outer side of the excitation coil, the coil sealing ring completely covers the excitation coil, and the outer diameter of the coil sealing ring is not greater than the maximum outer diameter of the piston core.

[0010] Preferably, a wire outlet hole is provided in the piston rod, an excitation coil lead is provided in the wire outlet hole, and the excitation coil lead is connected to the excitation coil.

[0011] Preferably, the piston assembly includes a piston core, the outer circumference of the piston core extends inwardly with a groove for installing the excitation coil, the piston core is provided with an annular flow channel, and the two ends of the piston core are respectively provided with a piston upper cover and a piston lower cover, an upper magnetic conductive plate is provided between the piston upper cover and the excitation coil, and a lower magnetic conductive plate is provided between the piston lower cover and the excitation coil, and the piston core is also provided with a piston outer tube, and the piston outer tube is slidably connected to the axial flow channel tube, and the piston upper cover and the piston lower cover are located in the piston outer tube, and the piston upper cover and the piston lower cover are abutted against the piston core through the piston outer tube.

[0012] Preferably, a coil sealing ring is provided between the excitation coil and the annular flow channel, and the coil sealing ring completely covers the excitation coil.

[0013] Preferably, a wire outlet hole is provided in the piston rod, an excitation coil lead is provided in the wire outlet hole, and the excitation coil lead passes through the wire outlet of the piston core and the wire outlet of the lower magnetic conductive plate to be connected to the excitation coil.

[0014] Preferably, a guide is further provided in the upper chamber, and the piston rod passes through the guide.

[0015] Preferably, a floating piston is further provided in the lower chamber, and a side of the floating piston away from the piston assembly forms an air cavity, and the air cavity is provided with an air charging and discharging port.

[0016] Beneficial technical effects of the present invention:

[0017] The present invention realizes position-sensitive characteristics by arranging an axial flow channel on the outer cylinder of the damper, and the width of the axial flow channel is different at different positions. The axial flow channel can use a single-rod structure, which not only solves the problem of radial offset of the piston of the traditional displacement-sensitive damper in the outer cylinder of the damper, but also increases the effective stroke of the position-sensitive damper. In addition, the axial flow channel can be processed by laser cutting a cylindrical hollow cylinder. Compared with the traditional position-sensitive damper that processes different inner diameters on the inner wall of the damper outer cylinder, the processing difficulty is greatly reduced, the cost is significantly reduced, and the processing accuracy requirements are reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 This is a schematic structural diagram of a damper with an axial flow channel capable of achieving position-sensitive characteristics according to Example 1 of the present invention;

[0019] Figure 2 This is a schematic structural diagram of the axial flow channel tube proposed in the present invention;

[0020] Figure 3 This is a schematic structural diagram of the piston assembly according to Example 1 of the present invention;

[0021] Figure 4 This is a schematic structural diagram of a damper with an axial flow channel capable of achieving position-sensitive characteristics according to Example 2 of the present invention;

[0022] Figure 5 This is a schematic structural diagram of the piston assembly of Example 2 proposed in the present invention.

[0023] In the figure: 1-excitation coil lead, 2-piston rod, 3-wire outlet, 4-guide, 5-damper outer tube, 6-axial flow channel tube, 7-upper chamber, 8-piston assembly, 801-piston core, 802-excitation coil, 803-coil sealing ring, 804-piston core end cover, 805-fastener, 806-piston lower cover, 807-piston core wire outlet, 808-piston outer tube, 809-lower magnetic conductive plate, 810-upper magnetic conductive plate, 811-piston upper cover, 812-annular flow channel, 9-axial flow channel, 10-lower chamber, 11-floating piston, 12-air cavity, 13-charging and discharging port. DETAILED DESCRIPTION

[0024] The present invention will be further explained below with reference to specific embodiments.

[0025] Example 1

[0026] Reference Figure 1The damper with an axial flow channel that can realize position-sensitive characteristics proposed by the present invention includes a damper outer tube 5, a piston assembly 8 is slidably connected to the damper outer tube 5, and the inner cavity of the damper outer tube 5 is divided into an upper chamber 7 and a lower chamber 10 by the piston assembly 8. The piston assembly 8 is located on one side of the upper chamber 7 and is provided with a piston rod 2. The end of the piston rod 2 away from the piston assembly 8 passes through the damper outer tube 5 and is located on the outside of the damper outer tube 5. An axial flow channel tube 6 is also provided between the damper outer tube 5 and the piston assembly 8. The axial flow channel tube 6 has a plurality of evenly distributed axial flow channels 9, and the width of the axial flow channels 9 is different at different positions; in the upper chamber 7, A guide 4 is also provided, and the piston rod 2 passes through the guide 4. The guide is provided with a dynamic seal and a guide sleeve between the guide and the piston rod; a floating piston 11 is also provided in the lower chamber 10, and the side of the floating piston 11 away from the piston assembly constitutes an air cavity 12, and the air cavity 12 is provided with an air charging and discharging port 13; the floating piston moves up and down slightly with the up and down movement of the piston core to compensate for the change in the volume of the piston rod in the outer tube of the damper during the up and down movement of the piston core, and non-magnetic aluminum alloy material can be used; the air cavity is filled with gas at a certain pressure to provide a certain pre-pressure to the upper and lower chambers, and at the same time compensate for the volume of the piston rod during the up and down movement of the piston.

[0027] Reference Figure 2 As a preferred solution of the present invention, the width of the axial flow channel 9 can be set to decrease from the middle to both ends, or other shapes of axial flow channels can be used. The specific shape can be designed according to actual needs; the axial flow channel tube is made of 304 stainless steel, which is non-magnetic, to prevent the magnetic field generated by the excitation coil from leaking through the axial flow channel tube.

[0028] Reference Figure 3 As a preferred embodiment of the present invention, the piston assembly 8 includes a piston core 801. A groove for mounting an excitation coil 802 extends inward from the outer circumference of the piston core 801. A piston core end cover 804 is provided on one side of the piston core 801 located at the lower chamber 10. The piston core end cover 804 is connected to the piston core 801 via a fastener (such as a fastening screw, etc.) 805. The piston core and the piston core end cover can be made of magnetically conductive 20# steel.

[0029] In addition, a coil sealing ring 803 is sheathed around the excitation coil 802, completely covering it. Its outer diameter is no larger than the maximum outer diameter of the piston core 801. The coil sealing ring forms an interference fit with the piston core and its end cap, and is coated with sealant at the joints to prevent magnetorheological fluid from entering the excitation coil. A wire outlet hole 3 is provided within the piston rod 2, housing the excitation coil lead 1, which is connected to the excitation coil 802.

[0030] The damping channel in this solution consists solely of the axial flow channel formed between the piston, the axial flow channel tube, and the damper outer tube. The axial flow channel is distributed throughout the entire stroke range, with the flow channel area being largest in the middle and gradually decreasing toward the ends. Furthermore, the magnetic field intensity of the axial flow channel can be adjusted by adjusting the current in the excitation coil in the piston, thereby changing the viscosity of the magnetorheological fluid. The damping adjustment of this damper is a combination of position and current control. The magnetic field generated by the excitation coil forms a circuit between the piston core, the piston core end cap, the axial flow channel, and the damper outer tube. The damper outer tube is made of a magnetically conductive material, while the axial flow channel tube is made of a non-magnetic material.

[0031] Example 2

[0032] Reference Figure 4 The damper with an axial flow channel that can realize position-sensitive characteristics proposed in the present invention includes a damper outer tube 5, and a piston assembly 8 is slidably connected inside the damper outer tube 5. The inner cavity of the damper outer tube 5 is divided into an upper chamber 7 and a lower chamber 10 by the piston assembly 8. The piston assembly 8 is located on one side of the upper chamber 7 and is provided with a piston rod 2. The end of the piston rod 2 away from the piston assembly 8 passes through the damper outer tube 5 and is located on the outside of the damper outer tube 5. An axial flow channel tube 6 is also provided between the damper outer tube 5 and the piston assembly 8. The axial flow channel tube 6 has a number of evenly distributed axial flow channels 9, and the width of the axial flow channels 9 is different at different positions. A guide 4 is also provided in the upper chamber 7, and the piston rod 2 passes through the guide 4. The guide is provided with a dynamic seal and a guide sleeve between the guide and the piston rod; a floating piston 11 is also provided in the lower chamber 10, and the side of the floating piston 11 away from the piston assembly constitutes an air cavity 12, and the air cavity 12 is provided with an air charging and discharging port 13; the floating piston moves up and down slightly with the up and down movement of the piston core to compensate for the change in the volume of the piston rod in the outer tube of the damper during the up and down movement of the piston core, and non-magnetic aluminum alloy material can be used; the air cavity is filled with gas at a certain pressure to provide a certain pre-pressure to the upper and lower chambers, and at the same time compensate for the volume of the piston rod during the up and down movement of the piston.

[0033] Reference Figure 2 As a preferred solution of the present invention, the width of the axial flow channel 9 can be set to decrease from the middle to both ends, or other shapes of axial flow channels can be used. The specific shape can be designed according to actual needs; the axial flow channel tube is made of 304 stainless steel, which is non-magnetic, to prevent the magnetic field generated by the excitation coil from leaking through the axial flow channel tube.

[0034] Reference Figure 5The piston assembly 8 includes a piston core 801, and a groove for installing the excitation coil 802 extends inward from the outer circumference of the piston core 801. An annular flow channel 812 is provided on the piston core 801. A piston upper cover 811 and a piston lower cover 806 are respectively provided at both ends of the piston core 801. An upper magnetic conductive plate 810 is provided between the piston upper cover 811 and the excitation coil 802, and a lower magnetic conductive plate 809 is provided between the piston lower cover 806 and the excitation coil 802. The piston core 801 is also sleeved with a piston outer tube 808, which is slidingly connected to the axial flow channel tube 6. The piston upper cover 811 and the piston lower cover 806 are located in the piston outer tube 808, and the piston upper cover 811 and the piston lower cover 806 are in contact with the piston core 801 through the piston outer tube 808.

[0035] A coil sealing ring 803 is provided between the excitation coil 802 and the annular flow channel 812. The coil sealing ring 803 completely covers the excitation coil 802. The coil sealing ring is interference fit with the upper magnetic conductive plate and the lower magnetic conductive plate, and sealing glue is applied at the fitting position to prevent magnetorheological fluid from entering the interior of the excitation coil.

[0036] The piston rod 2 is provided with a wire outlet hole 3 , in which an excitation coil lead 1 is provided. The excitation coil lead 1 passes through the piston core wire outlet 807 and the wire outlet of the lower magnetic conductive plate 809 and is connected to the excitation coil 801 .

[0037] The axial flow channel on the axial flow channel tube of the present invention is only distributed in the middle area of ​​the damper stroke, and an annular flow channel is provided on the piston. In the middle area, the flow channel area of ​​the damper is the area of ​​the axial flow channel plus the area of ​​the annular flow channel. At this time, the area of ​​the damping channel is large and the damping coefficient is small. When the piston moves to an area without an axial flow channel, only the annular flow channel in the piston serves as the damping channel. At this time, the area of ​​the damping channel is small and the damping coefficient is large. Within the entire stroke range, the viscosity of the magnetorheological fluid at the annular flow channel and the damping coefficient can be adjusted by adjusting the current of the excitation coil in the piston. The magnetic field generated by the excitation coil forms a loop between the lower magnetic plate, the piston outer tube, the upper magnetic plate, the annular flow channel, the piston core and the lower magnetic plate. The axial flow channel tube and the damper outer tube are made of non-magnetic materials.

Claims

1. A damper having an axial flow channel capable of realizing position-sensitive characteristics, characterized in that: The invention comprises a damper outer tube (5), wherein a piston assembly (8) is slidably connected to the damper outer tube (5), and the inner cavity of the damper outer tube (5) is divided into an upper chamber (7) and a lower chamber (10) by the piston assembly (8); a piston rod (2) is provided on one side of the piston assembly (8) located in the upper chamber (7); an end of the piston rod (2) away from the piston assembly (8) passes through the damper outer tube (5) and is located outside the damper outer tube (5); an axial flow channel tube (6) is further provided between the damper outer tube (5) and the piston assembly (8); the axial flow channel tube (6) is provided with a plurality of evenly distributed axial flow channels (9); and the width of the axial flow channels (9) is different at different positions; The piston assembly (8) includes a piston core (801), the outer circumference of the piston core (801) extends inwardly to form a groove for mounting an excitation coil (802), an annular flow channel (812) is provided on the piston core (801), and the two ends of the piston core (801) are respectively provided with a piston upper cover (811) and a piston lower cover (806), an upper magnetic conductive plate (810) is provided between the piston upper cover (811) and the excitation coil (802), and the piston lower cover (806) is provided with a magnetic conductive plate (810). 6) is provided with a lower magnetic conductive plate (809) between the piston core (801) and the excitation coil (802), the piston core (801) is also provided with a piston outer tube (808), the piston outer tube (808) is slidably connected to the axial flow channel tube (6), the piston upper cover (811) and the piston lower cover (806) are located in the piston outer tube (808), and the piston upper cover (811) and the piston lower cover (806) are abutted against the piston core (801) through the piston outer tube (808).

2. The damper having an axial flow channel capable of realizing position-sensitive characteristics according to claim 1, characterized in that: The width of the axial flow channel (9) decreases from the middle to both ends.

3. The damper having an axial flow channel capable of realizing position-sensitive characteristics according to claim 1, characterized in that: A coil sealing ring (803) is provided between the excitation coil (802) and the annular flow channel (812), and the coil sealing ring (803) completely covers the excitation coil (802).

4. The damper having an axial flow channel capable of realizing position-sensitive characteristics according to claim 1, characterized in that: The piston rod (2) is provided with a wire outlet hole (3), an excitation coil lead (1) is provided in the wire outlet hole (3), and the excitation coil lead (1) passes through the piston core wire outlet (807) and the wire outlet of the lower magnetic conductive plate (809) to be connected to the excitation coil (801).

5. The damper having an axial flow channel capable of realizing position-sensitive characteristics according to claim 1, characterized in that: A guide (4) is also provided in the upper chamber (7), and the piston rod (2) passes through the guide (4).

6. The damper having an axial flow channel capable of realizing position-sensitive characteristics according to claim 1, characterized in that: A floating piston (11) is further provided in the lower chamber (10), and a side of the floating piston (11) away from the piston assembly forms an air cavity (12), and the air cavity (12) is provided with an air charging and discharging port (13).

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