Magneto-rheological damping seat cushion

Abstract

The magnetorheological damping seat cushion comprises a seat cushion body and a cylinder barrel, the seat cushion body comprises a seat cushion body and an air bag part arranged in the seat cushion body, a containing cavity is formed in the air bag part, and the air bag part can expand or contract to change the height of the seat cushion body; the cylinder barrel is arranged below the cushion, a hydraulic cavity and a magnetorheological valve are arranged on the cylinder barrel, the hydraulic cavity communicates with the containing cavity, magnetorheological fluid capable of being driven to flow is stored in the hydraulic cavity, the air bag part is expanded or contracted through flowing of the magnetorheological fluid, and a magnet exciting coil is arranged on the magnetorheological valve. The magnetic field intensity is controlled through the current of the magnet exciting coil to achieve damping force adjustment. The magnet exciting coil on the magneto-rheological valve is electrified to generate a magnetic field, the magneto-rheological fluid presents the characteristics of high viscosity and low fluidity through magnetization of the magnetic field, damping force is provided, meanwhile, the magneto-rheological fluid is pushed to enter the cushion through the connecting pipe, the size of the air bag part in the cushion is changed, and therefore the height of the single side of the cushion is changed, and the overall vibration reduction effect is achieved.

Description

Technical Field

[0001] The invention relates to the technical field of vibration suppression, and in particular to a magnetorheological vibration damping cushion. Background Art

[0002] With the improvement of vehicle intelligence, vehicles will become mobile offices. With the promotion of zero-gravity seats, the vibration reduction effect of traditional passenger car seats is difficult to meet. In addition, as vehicles develop towards high speed and heavy load, they bring great vibration and impact to passengers and cargo, seriously affecting the comfort of drivers and passengers and the safety of cargo. Usually, several levels of vibration reduction measures are adopted, such as suspension vibration reduction, seat vibration reduction, etc. However, due to space restrictions or national safety regulations, hydraulic vibration reduction is rarely used in passenger car seats. It only relies on chassis vibration reduction, seats with foam structure or by adding vibration absorbers to improve the vibration reduction effect, but it is impossible to achieve better vibration reduction effect in a wide frequency range.

[0003] Therefore, in response to the current problems of poor vibration reduction effect and inability to perform dynamic posture adjustment in passenger car seats, there is an urgent need to design a magic cushion based on magnetorheological technology, which has a simple structure and can be installed independently or integrated with the seat. Summary of the invention

[0004] In view of this, the present invention provides a magnetorheological vibration-damping seat cushion, which utilizes magnetorheological technology to innovate in vibration-damping principles and implementation structures, has a simple structure, and can be installed independently or integrated with a seat.

[0005] The magnetorheological vibration damping seat cushion provided by the present invention adopts the following technical solution:

[0006] A magnetorheological vibration damping seat cushion, comprising:

[0007] A seat cushion, comprising a seat cushion body and an airbag portion disposed inside the seat cushion body, wherein the airbag portion has a receiving chamber for receiving a magnetorheological fluid, and the airbag portion can expand or contract to change the height of a corresponding portion of the seat cushion body;

[0008] A cylinder barrel is arranged below the seat cushion, a hydraulic chamber and a magnetorheological valve are arranged on the cylinder barrel, the hydraulic chamber is in communication with the accommodating chamber, a magnetorheological fluid that can be driven to flow is stored in the hydraulic chamber, the airbag portion is expanded or contracted by the flow of the magnetorheological fluid, an excitation coil is arranged on the magnetorheological valve, and the magnetic field strength is controlled by the current size of the excitation coil to achieve damping force adjustment.

[0009] Optionally, a plurality of hydraulic chambers are distributed along the axial direction of the cylinder, and adjacent hydraulic chambers are separated by floating pistons or magnetorheological valves.

[0010] Optionally, a main piston is slidingly arranged in the cylinder, and the cylinder is divided into multiple chambers by a floating piston, a magnetorheological valve and a main piston. The magnetorheological valve and the floating piston are symmetrically distributed in the cylinder with the radial direction of the main piston as the symmetry axis. The floating piston is arranged close to the main piston relative to the magnetorheological valve, and the main piston can be driven to move so as to squeeze the corresponding chamber.

[0011] Optionally, piston rods are provided on both sides of the main piston along the axial direction of the cylinder, and the piston rods extend outward from the cylinder. The piston rods can be manipulated to move along the axial direction of the cylinder to drive the main piston to squeeze the corresponding chamber so that the corresponding airbag part expands or contracts.

[0012] Optionally, the cylinder is divided into six chambers by a floating piston, a magnetorheological valve and a main piston, the floating piston includes a floating piston 1 and a floating piston 2, the magnetorheological valve includes a magnetorheological valve 1 and a magnetorheological valve 2, the hydraulic chamber includes chamber 1, chamber 2, chamber 3, chamber 4, chamber 5 and chamber 6 distributed from left to right, chamber 1 and chamber 2 are separated by a magnetorheological valve 1, chamber 2 and chamber 3 are separated by a floating piston 1, chamber 3 and chamber 4 are separated by a main piston, chamber 4 and chamber 5 are separated by a floating piston 2, and chamber 5 and chamber 6 are separated by a magnetorheological valve 2.

[0013] Optionally, a magnetic flow channel for magnetorheological fluid to flow is formed between the magnetorheological valve and the inner wall of the cylinder, the magnetorheological fluid is filled in chamber one, chamber two, chamber five and chamber six, and chamber three and chamber four are filled with gas.

[0014] Optionally, the airbag array is disposed in the cushion body, the accommodating chambers of adjacent airbags are in communication with each other, and the accommodating chamber of the airbag located at the end is in communication with the hydraulic chamber via a connecting pipe.

[0015] Optionally, a floating piston guide belt is provided between the floating piston and the inner wall of the cylinder, and a piston guide belt is provided between the piston and the inner wall of the cylinder.

[0016] Optionally, a sealing ring is provided at the connection between the floating piston and the magnetorheological valve and the piston rod.

[0017] Optionally, a screw motor is also included. A nut is provided on the main piston. The piston rod is threadedly connected to the nut. The screw motor is used to drive the piston rod to rotate so as to drive the nut to move along the axial direction of the piston rod.

[0018] In summary, the present invention includes at least one of the following beneficial technical effects: the excitation coil on the magnetorheological valve generates a magnetic field after being energized, and the magnetorheological fluid exhibits the characteristics of high viscosity and low fluidity after being magnetized by the magnetic field, providing damping force for the entire structure, and at the same time pushing the magnetorheological fluid into the seat cushion through the connecting pipe, changing the volume of the airbag part in the seat cushion, thereby changing the height of one side of the seat cushion, achieving an overall vibration reduction effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 is a schematic diagram of the overall structure of an embodiment of the present invention;

[0020] Figure 2 is a schematic structural diagram of a seat cushion according to an embodiment of the present invention;

[0021] Figure 3 Schematic diagram of the structure of the cylinder barrel of the embodiment of the present invention Figure 1 ;

[0022] Figure 4 It is a schematic diagram of the structure in which the screw motor of an embodiment of the present invention pushes the piston to move leftward;

[0023] Figure 5 Schematic diagram of the structure of a magnetorheological valve according to an embodiment of the present invention Figure 2 ;

[0024] Figure 6 Schematic diagram of the structure of a cylinder barrel according to an embodiment of the present invention.

[0025] Explanation of the reference numerals in the accompanying drawings: 1. airbag part; 2. connecting pipe; 3. cylinder; 4. piston rod sealing ring; 5. piston rod; 6. magnetorheological valve sealing ring; 7. magnetorheological valve two; 8. excitation coil; 9. floating piston two; 10. piston sealing ring; 11. floating piston guide belt; 12. piston guide belt; 13. main piston; 14. floating piston one; 15. magnetorheological valve one; 16. chamber one; 17. chamber two; 18. chamber three; 19. chamber four; 20. chamber five; 21. chamber six; 22. seat cushion. DETAILED DESCRIPTION

[0026] The following is combined with Figure 1-6 The present invention is described in further detail.

[0027] The embodiment of the invention discloses a magnetorheological vibration-damping seat cushion.

[0028] Reference Figure 1 , Figure 2 , Figure 3 , Figure 4 , Figure 5 , Figure 6A magnetorheological vibration damping seat cushion comprises a seat cushion 22 and a cylinder 3. The seat cushion 22 comprises a seat cushion 22 body and an airbag portion 1 arranged inside the seat cushion 22 body. The airbag portion 1 has a containing chamber for containing magnetorheological fluid. The airbag portion 1 can expand or contract to change the height of the corresponding part of the seat cushion 22 body; the cylinder 3 is arranged below the seat cushion 22, and a hydraulic chamber and a magnetorheological valve are arranged on the cylinder 3. The hydraulic chamber communicates with the containing chamber, and magnetorheological fluid that can be driven to flow is stored in the hydraulic chamber. The airbag portion 1 is expanded or contracted by the flow of the magnetorheological fluid. An excitation coil 8 is arranged on the magnetorheological valve, and the magnetic field strength is controlled by the current size of the excitation coil 8 to achieve damping force adjustment. When the excitation coil 8 on the magnetorheological valve is energized, a magnetic field is generated. The magnetorheological fluid exhibits the characteristics of high viscosity and low fluidity after being magnetized by the magnetic field, providing damping force for the entire structure and at the same time pushing the magnetorheological fluid into the seat cushion 22 through the connecting pipe 2, changing the volume of the airbag part 1 in the seat cushion 22, thereby changing the height of one side of the seat cushion 22, achieving an overall vibration reduction effect.

[0029] The seat cushion 22 body is an elastic body. In the present embodiment, the seat cushion 22 body is a foam seat cushion 22. The seat cushion 22 body can be integrated into the seat or installed independently.

[0030] In this embodiment, the airbag part 1 is a flexible sac, and the accommodating chamber is located in the center of the flexible sac. The number of airbags can be customized and designed according to the needs of the user. The number and size of the airbags under different working conditions can be changed. Specifically, the airbag part 1 array is arranged in the seat cushion 22 body, and the accommodating chambers of adjacent airbag parts 1 are in communication with each other. The accommodating chamber of the airbag part 1 at the end is in communication with the hydraulic chamber through the connecting pipe 2. It is composed of m×n airbag parts 1, where m and n>1. The airbag part 1 is arranged in the seat cushion 22 body to expand or contract the seat cushion 22 body. The airbag part 1 can be embedded in the seat cushion 22 body to adjust the height comfort of the seat cushion 22 body.

[0031] By adjusting the pressure of the airbag part 1, different heights can be achieved to meet the comfort of different people with different body shapes. For example, compared with the adult seat cushion 22, the airbag part 1 of the child seat cushion 22 has a smaller inflated volume and a shorter height to meet the comfort of children.

[0032] In this embodiment, a threaded opening is embedded in the front of the airbag part 1 for connecting with the connecting pipe 2. Specifically, the connecting pipe 2 is a high-pressure pipe for replenishing the magnetorheological fluid. The connecting pipe 2 is connected to the hydraulic chamber of the lower cylinder 3 to provide damping force.

[0033] There are multiple hydraulic chambers distributed along the axial direction of the cylinder 3, and adjacent hydraulic chambers are separated by floating pistons or magnetorheological valves.

[0034] A main piston 13 is provided in a sliding manner in the cylinder 3, and the cylinder 3 is divided into left and right sides by the main piston 13, and the structures of the left and right sides are symmetrical. Specifically, the cylinder 3 is divided into multiple chambers by the floating piston, the magnetorheological valve and the main piston 13, and the magnetorheological valve and the floating piston are symmetrically distributed in the cylinder 3 with the radial direction of the main piston 13 as the symmetry axis. The floating piston is arranged close to the main piston 13 relative to the magnetorheological valve, and the main piston 13 can be driven to squeeze the corresponding chamber.

[0035] The main piston 13 is provided with piston rods 5 on both sides of the cylinder 3 axially. The piston rods 5 extend outward from the cylinder 3 . The piston rods 5 can be manipulated to move axially along the cylinder 3 to drive the main piston 13 to squeeze the corresponding chamber so that the corresponding airbag part 1 expands or contracts.

[0036] The cylinder 3 is divided into six chambers by a floating piston, a magnetorheological valve and a main piston 13. The floating piston includes a floating piston 14 and a floating piston 2 9. The magnetorheological valve includes a magnetorheological valve 15 and a magnetorheological valve 2 7. The hydraulic chamber includes a chamber 16, a chamber 2 17, a chamber 3 18, a chamber 4 19, a chamber 5 20 and a chamber 6 21 which are distributed from left to right. The chamber 1 16 and the chamber 2 17 are separated by a magnetorheological valve 1 15, the chamber 2 17 and the chamber 3 18 are separated by a floating piston 14, the chamber 3 18 and the chamber 4 19 are separated by the main piston 13, the chamber 4 19 and the chamber 5 20 are separated by a floating piston 2 9, and the chamber 5 20 and the chamber 6 21 are separated by a magnetorheological valve 2 7.

[0037] Reference Figure 1 , Figure 3 , Figure 4 , Figure 5 , Figure 6 A magnetic flow channel for magnetorheological fluid to flow is formed between the magnetorheological valve and the inner wall of the cylinder 3. The magnetorheological fluid is filled in chamber 16, chamber 2 17, chamber 5 20 and chamber 6 21. Chamber 1 16 is separated from the adjacent chamber 2 17 by magnetorheological valve 1 15, and chamber 6 21 is separated from the adjacent chamber 5 20 by magnetorheological valve 2 7. Magnetorheological fluid is filled in chamber 1 16, chamber 2 17, chamber 5 20 and chamber 6 21 to provide damping force. An excitation coil 8 is wound between the magnetorheological valve 1 15 and the magnetorheological valve 2 7 to provide a magnetic field. The magnetorheological fluid can flow through the corresponding magnetorheological valve through the side gap. When the excitation coil 8 is energized, a magnetic field is generated around it, which changes the characteristics of the magnetorheological fluid, increases the damping force, and realizes the change of the damping characteristics, which can change the properties of the magnetorheological fluid, thereby increasing the damping force. Similarly, chamber five 20 and chamber six 21 are also filled with magnetorheological fluid, and their functions are the same.

[0038] Chamber three 18 and chamber four 19 are filled with gas. Specifically, the gas is preferably an inert gas. Further, the gas is nitrogen. Specifically, chamber three 18 is filled with nitrogen and is separated from chamber two 17 by floating piston one 14. The floating piston is provided with a floating piston guide belt 11 in the circumference to avoid direct friction between the floating piston and the inner wall of the cylinder 3. The radial changes in vibration performance can be absorbed at any time to improve the vibration reduction effect. A sealing ring is provided at the connection between the floating piston and the magnetorheological valve and the piston rod 5. Specifically, a piston sealing ring 10 is provided between the floating piston and the piston rod 5. The setting of the piston sealing ring 10 can effectively prevent the gas from mixing with the magnetorheological fluid and improve the sealing performance. The structure of chamber four 19 is similar.

[0039] Reference Figure 1 , Figure 3 , Figure 4 , Figure 5 , Figure 6 A magnetorheological valve sealing ring 6 is arranged between the magnetorheological valve and the piston rod 5. The arrangement of the magnetorheological valve sealing ring 6 improves the sealing performance and the damping effect.

[0040] A piston guide belt 12 is provided between the main piston 13 and the inner wall of the cylinder barrel 3. The piston guide belt 12 is installed on the main piston 13. The piston guide belt 12 can play a guiding role in preventing the oil cylinder and the piston rod 5 from being worn and protecting the seal of the seal. It can absorb radial changes in vibration performance at any time to improve the vibration reduction effect. The piston guide belt 12 can avoid direct contact between the main piston 13 in the cylinder and the cylinder barrel 3.

[0041] Reference Figure 1 , Figure 2 , Figure 3 , Figure 4 , Figure 5 , Figure 6 The piston rod 5 can be manipulated to move along the axial direction of the cylinder 3 to drive the main piston 13 to squeeze the corresponding chamber so that the corresponding airbag part 1 expands or contracts. In this embodiment, the piston rod 5 is manipulated by the screw motor to move along the axial direction of the cylinder 3. Specifically, a nut is fixedly provided on the main piston 13, and the main piston 13 is restricted to rotate along its circumferential direction. The main piston 13 can only move along the axial direction of the cylinder 3. The piston rod 5 is threadedly connected with the nut. The screw motor is used to drive the piston rod 5 to rotate so as to drive the nut to move along the axial direction of the piston rod 5. The piston rod 5 adopts a screw motor structure to lift the middle main piston 13, thereby controlling the flow of the magnetorheological fluid, and then adjusting the volume of the airbag part 1 to achieve the effect of roll vibration reduction.

[0042] Reference Figure 1 , Figure 3For example, when the screw motor pushes the main piston 13 to move to the left, the main piston 13 compresses the gas in the chamber three 18, generates a leftward force F2, pushes the floating piston 14 to move to the left, squeezes the magnetorheological fluid in the chamber two 17 to flow through the magnetorheological valve to the chamber one 16, flows into the high-pressure pipe through the upper pipe joint, and then enters the upper airbag part 1, changes the height of the left seat cushion 22 body, and balances the discomfort caused to the human body when turning. Similarly, the screw motor pushes the main piston 13 to move to the right.

[0043] The piston rod 5 of the cylinder 3 adopts a double-rod main piston 13, which is connected to the middle main piston 13. The piston rod 5 adopts a screw structure, which is externally connected to a control motor. The nut matches the thread on the screw, and is usually made of metal or plastic. When the screw rotates, the nut slides on the thread on the screw, thereby achieving linear motion. The motor can drive the piston rod 5 to move left and right to adjust the height of the seat cushion 22.

[0044] By controlling the forward and reverse rotation of the motor, the screw rod pushes or stretches the piston rod 5, squeezing the nitrogen in the middle cavity to push the floating pistons on both sides, thereby realizing the flow of the magnetorheological fluid. The energization of the excitation coil 8 on the magnetorheological valve generates a magnetic field. The magnetorheological fluid exhibits high viscosity and low fluidity after being magnetized by the magnetic field, providing damping force for the entire structure. At the same time, the magnetorheological fluid is pushed into the seat cushion 22 through the connecting pipe 2, changing the volume of the airbag part 1 in the upper seat cushion 22, thereby changing the height of one side, achieving the effect of overall vibration reduction.

[0045] The accommodating chamber of the airbag part 1 is filled with magnetorheological fluid to play a role in vibration reduction and buffering. When the user is subjected to vertical vibration, the airbag part 1 and the magnetorheological fluid therein can achieve the vibration reduction effect through compression. In addition, when the force on both sides is unbalanced, such as when the car is turning, by adjusting the displacement of the main piston 13 of the double-rod hydraulic cylinder below, the discomfort caused to the driver by the centripetal force generated by the vehicle's roll can be compensated, further improving the vibration reduction effect and improving comfort.

[0046] In this embodiment, the overall model structure can be approximated as a single-degree-of-freedom model, with the output above the seat cushion 22, and a stiffness and a damping in parallel in the middle, which is equivalent to a mass damping elastic model. The stiffness can be changed by changing the volume of the magnetorheological fluid of the airbag part 1, and the damping can be controlled by adjusting the current of the magnetorheological valve. Among them, the above-mentioned single-degree-of-freedom model can use a ceiling control algorithm or a fuzzy control algorithm, and the value of the control force can be changed by adjusting the size of the damping coefficient, which can achieve a good vibration reduction effect and significantly improve the comfort of use.

[0047] The present invention combines the traditional seat cushion 22 with the idea of ​​oil and gas spring to achieve the effect of vibration reduction and buffering. The seat cushion 22 of the present invention is embedded in the foam interlayer inside the seat, and the height of both sides can be adjusted separately to achieve vibration reduction in multiple positions. A hydraulic cylinder is connected to the foam seat cushion 22 with the airbag part 1 to achieve the change of stiffness and damping. The magnetorheological fluid is filled into the airbag part 1 by squeezing the floating piston to change its stiffness and adjust the comfort. A magnetorheological valve is used in the cylinder 3, and magnetorheological fluid is added. The floating piston promotes the flow of the magnetorheological fluid, and the magnetorheological fluid flows through the magnetorheological valve to provide damping force to the system. The position of the floating piston is adjusted by driving the screw rod to rotate using a motor, so as to achieve the change of the magnetorheological fluid in the cylinder 3 in a short time, which can cope with larger vibration effects. A double-rod hydraulic cylinder is used to divide the airbag part 1 in the upper seat cushion 22 into two parts, so as to achieve separate control and adapt to vibration reduction during roll.

Claims

1. A magnetorheological vibration damping seat cushion, characterized in that: include: A seat cushion, comprising a seat cushion body and an airbag portion disposed inside the seat cushion body, wherein the airbag portion has a receiving chamber for receiving a magnetorheological fluid, and the airbag portion can expand or contract to change the height of a corresponding portion of the seat cushion body; A cylinder barrel is arranged below the seat cushion, a hydraulic chamber and a magnetorheological valve are arranged on the cylinder barrel, the hydraulic chamber is in communication with the accommodating chamber, a magnetorheological fluid that can be driven to flow is stored in the hydraulic chamber, the airbag portion is expanded or contracted by the flow of the magnetorheological fluid, an excitation coil is arranged on the magnetorheological valve, and the magnetic field strength is controlled by the current size of the excitation coil to achieve damping force adjustment.

2. The magnetorheological damping seat cushion according to claim 1 is characterized in that: There are a plurality of hydraulic chambers distributed along the axial direction of the cylinder barrel, and adjacent hydraulic chambers are separated by floating pistons or magnetorheological valves.

3. The magnetorheological vibration damping cushion according to claim 2 is characterized in that: A main piston is slidingly arranged in the cylinder, and the cylinder is divided into multiple chambers by a floating piston, a magnetorheological valve and a main piston. The magnetorheological valve and the floating piston are symmetrically distributed in the cylinder with the radial direction of the main piston as the symmetry axis. The floating piston is arranged close to the main piston relative to the magnetorheological valve, and the main piston can be driven to move to squeeze the corresponding chamber.

4. The magnetorheological vibration damping cushion according to claim 3 is characterized in that: The main piston is provided with piston rods on both sides of the cylinder along the axial direction. The piston rods extend outward from the cylinder. The piston rods can be manipulated to move along the axial direction of the cylinder to drive the main piston to squeeze the corresponding chamber so that the corresponding airbag part expands or contracts.

5. The magnetorheological vibration damping cushion according to claim 4 is characterized in that: The cylinder is divided into six chambers by a floating piston, a magnetorheological valve and a main piston. The floating piston includes a floating piston 1 and a floating piston 2. The magnetorheological valve includes a magnetorheological valve 1 and a magnetorheological valve 2. The hydraulic chamber includes chamber 1, chamber 2, chamber 3, chamber 4, chamber 5 and chamber 6, which are distributed from left to right. Chamber 1 and chamber 2 are separated by a magnetorheological valve 1, chamber 2 and chamber 3 are separated by a floating piston 1, chamber 3 and chamber 4 are separated by a main piston, chamber 4 and chamber 5 are separated by a floating piston 2, and chamber 5 and chamber 6 are separated by a magnetorheological valve 2.

6. The magnetorheological damping cushion according to claim 5, characterized in that: A magnetic flow channel for magnetorheological fluid to flow is formed between the magnetorheological valve and the inner wall of the cylinder. The magnetorheological fluid is filled in chamber one, chamber two, chamber five and chamber six, and chamber three and chamber four are filled with gas.

7. The magnetorheological vibration damping cushion according to claim 1, characterized in that: The airbag array is arranged in the seat cushion body, the accommodating chambers of adjacent airbags are in communication with each other, and the accommodating chamber of the airbag located at the end is in communication with the hydraulic chamber through a connecting pipe.

8. The magnetorheological vibration damping cushion according to claim 3 is characterized in that: A floating piston guide belt is arranged between the floating piston and the inner wall of the cylinder, and a piston guide belt is arranged between the main piston and the inner wall of the cylinder.

9. The magnetorheological vibration damping cushion according to claim 3 is characterized in that: It also includes a screw motor. A nut is arranged on the main piston. The piston rod is threadedly connected with the nut. The screw motor is used to drive the piston rod to rotate so as to drive the nut to move along the axial direction of the piston rod.

10. The magnetorheological vibration damping cushion according to claim 3, characterized in that: The connection between the floating piston and the magnetorheological valve and the piston rod is provided with a sealing ring.

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