Magnetorheological fluid buffer

Abstract

The utility model provides a magnetorheological fluid buffer which comprises a body, an end cover, a guide bearing and an isolation end cover, a one-way valve is arranged in the isolation end cover, a pressure pipe is arranged between the isolation end cover and the guide bearing, a first liquid storage cavity is formed between the pressure pipe and the body, a piston is connected in the pressure pipe, a pressure cavity is formed between the pressure pipe and the piston, and a magnet exciting coil is nested in the piston. A liquid passing gap is formed between the piston and the pressure pipe and communicated with the first liquid storage cavity, the piston is connected with the piston rod, the piston rod is hollow, a wire is connected in the piston rod and electrically connected with the magnet exciting coil, a throttling hole and a backflow hole are formed in the pressure pipe, and the liquid passing gap is communicated with the throttling hole and the backflow hole. The isolation end cover is provided with a liquid passing channel communicated with the first liquid storage cavity, a floating piston is arranged in the body and located between the end cover and the isolation end cover, a nitrogen cavity is formed between the floating piston and the end cover, a second liquid storage cavity is formed between the floating piston and the isolation end cover, and the second liquid storage cavity is communicated with the first liquid storage cavity through the liquid passing channel.

Description

Technical Field

[0001] The utility model relates to the technical field of buffers, in particular to a magnetorheological fluid buffer. Background Art

[0002] Industrial hydraulic buffers are energy absorbing elements used in the automation industry. They can absorb the kinetic energy of moving objects and slow them down and stop them steadily. They can improve production efficiency and extend the life of equipment. Hydraulic buffers are divided into adjustable and non-adjustable types. The non-adjustable type means that the damping effect of the buffer is fixed and there is no flow adjustment hole in the oil circuit. The adjustable buffer has a flow adjustment hole inside, which can adjust the cross-sectional area of ​​the flow hole, thereby adjusting the flow size and realizing the change of the damping force.

[0003] With the changes in market personalized needs and changes in the industry, mass production has shifted to small-batch diversified customization. Under the new market demands, product lines need to be frequently adjusted to meet market needs. The existing adjustable hydraulic buffers adjust the damping force by manually adjusting the flow control knob. The entire production line is spread across many buffers, which greatly increases the time for production line changes and debugging. Utility Model Content

[0004] The utility model aims to provide a magnetorheological fluid buffer to overcome the deficiencies in the prior art.

[0005] In order to solve the above technical problems, the technical solution of the utility model is: a magnetorheological fluid buffer, including a body, end covers and guide bearings are correspondingly arranged at both ends of the body, an isolation end cover is arranged in the body, a one-way valve is arranged in the isolation end cover, a pressure tube is arranged between the isolation end cover and the guide bearing, a first liquid storage cavity is formed between the pressure tube and the body, a piston is connected in the pressure tube, a pressure cavity is formed between the pressure tube and the piston, an excitation coil is nested in the piston, a liquid gap is formed between the piston and the pressure tube, and the liquid gap is connected to the first liquid storage cavity, The piston is connected to a piston rod, which is hollow. A wire is connected inside the piston rod, which is electrically connected to the excitation coil. A throttling hole and a reflux hole are provided on the pressure tube, wherein the liquid gap is connected to the throttling hole and the reflux hole. The isolation end cover is provided with a liquid passage connected to the first liquid storage chamber. A floating piston is provided in the body, and the floating piston is located between the end cover and the isolation end cover. A nitrogen cavity is formed between the floating piston and the end cover. A second liquid storage chamber is formed between the floating piston and the isolation end cover, and the second liquid storage chamber is connected to the first liquid storage chamber through the liquid passage.

[0006] In the above scheme, when the piston rod is hit by an external force, the piston rod drives the piston to move toward the isolation end cover, forcing the magnetorheological fluid to flow out through the throttling hole arranged on the pressure tube and the annular liquid gap between the piston and the pressure tube, and flow into the first liquid storage chamber between the pressure tube and the body, and then flow into the second liquid storage chamber through the annular liquid passage on the isolation end cover. The floating piston is pushed by the magnetorheological fluid and moves to the left, squeezing the nitrogen in the nitrogen chamber to accumulate pressure. As the piston gradually moves to the left, the preset throttling hole is gradually closed, and the damping force increases accordingly, resulting in specific damping characteristics. When the load is removed, the accumulated pressure of the nitrogen will push the liquid through the one-way valve in the middle of the isolation end cover, the throttling hole of the inner tube, and the annular liquid gap between the piston and the pressure tube to flow back to the pressure chamber, completing a working cycle. When damping adjustment is required, the wire is connected to the PID control unit, and the current input to the wire is adjusted through the PID control unit. The wire inputs the current to the excitation coil to generate a magnetic field. The excitation coil generates different magnetic field strengths according to the size of the input current, which in turn affects the pressure intensity and the annular liquid gap between the pistons, causing its shape to change and slowing down its passing speed to achieve the adjustment of the damping force.

[0007] As an improvement of the magnetorheological fluid buffer of the utility model, the tail end of the piston rod is provided with an impact head and an impact head end cover, wherein the impact head is provided with a through hole for the wire to pass through.

[0008] In the above scheme, in order to reduce the loss of the piston rod, an impact head is added to replace the piston rod to withstand the impact. At the same time, since the wires need to be introduced from both ends of the piston rod, in order to avoid squeezing the wires and causing the wires to break when hitting the impact head, a through hole for leading out the wires is provided on the side of the impact head to lead out the wires, so that the wires come out from the side of the impact head, thereby protecting the wires. At the same time, the impact head end cover cooperates with the impact head to withstand the impact.

[0009] As an improvement of the magnetorheological fluid buffer of the utility model, the one-way valve in the isolation end cover is equipped with a reset spring.

[0010] In the above scheme, when the load is removed, the accumulated pressure of the nitrogen will push the liquid back to the pressure chamber through the one-way valve in the middle of the isolation end cover, the throttling hole of the inner tube and the annular liquid gap between the piston and the pressure tube, completing a working cycle. However, during this working cycle, the one-way valve moves a certain distance under pressure. After the working cycle is completed, the one-way valve loses pressure and is pushed by the reset spring to reset the pressure.

[0011] As an improvement of the magnetorheological fluid buffer of the utility model, the piston is provided with a notch for facilitating the connection between the wire and the excitation coil.

[0012] In the above scheme, the original piston structure wraps the two ends of the excitation coil, which makes it troublesome to connect the wire and the excitation coil. Therefore, the original piston structure needs to be adjusted to facilitate the electrical connection between the wire and the excitation coil. Therefore, the piston is provided with a notch for facilitating the connection between the wire and the excitation coil.

[0013] Compared with the prior art, the utility model has the following beneficial effects: when damping adjustment is required, the wire can be connected to the PID control unit, first the damping force and current of the damper in different production modes are calibrated, and then the current input to the wire is adjusted by the preset production mode or PID control algorithm, the current is transmitted to the excitation coil through the wire to generate the magnetic field strength, and the magnetorheological fluid is affected by the magnetic field when passing through the annular liquid gap between the pressure tube and the piston, and the flow state changes, the flow rate of the magnetorheological fluid passing through slows down, and the damping force is adjusted. This scheme can realize remote and multi-end damping control through the control end. The PID control unit can also be connected through the wire to complete the closed loop and realize the semi-active control of the buffer. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0015] Figure 1 It is a schematic diagram of the structure of a magnetorheological fluid buffer;

[0016] Figure 2 for Figure 1 Enlarged view of point A.

[0017] Among them, 1. body; 2. end cover; 3. guide bearing; 4. isolation end cover; 5. one-way valve; 6. pressure tube; 7. first liquid storage chamber; 8. piston; 9. pressure chamber; 10. excitation coil; 11. liquid gap; 12. piston rod; 13. wire; 14. throttle hole; 15. reflux hole; 16. liquid passage; 17. floating piston; 18. nitrogen cavity; 19. second liquid storage chamber; 20. impact head; 21. impact head end cover; 22. through hole; 23. reset spring; 24. notch. DETAILED DESCRIPTION

[0018] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0019] like Figure 1 and 2 As shown, a magnetorheological fluid buffer includes a body 1, end covers 2 and guide bearings 3 are correspondingly arranged at both ends of the body 1, an isolation end cover 4 is arranged in the body 1, a one-way valve 5 is arranged in the isolation end cover 4, a pressure tube 6 is arranged between the isolation end cover 4 and the guide bearing 3, a first liquid storage chamber 7 is formed between the pressure tube 6 and the body 1, a piston 8 is connected in the pressure tube 6, a pressure chamber 9 is formed between the pressure tube 6 and the piston 8, an excitation coil 10 is nested in the piston 8, a liquid gap 11 is formed between the piston 8 and the pressure tube 6, the liquid gap 11 is connected to the first liquid storage chamber 7, the piston 8 is connected to a piston rod 12, and the piston rod 12 is hollow A conducting wire 13 is connected inside the piston rod 12, and the conducting wire 13 is electrically connected to the excitation coil 10; a throttling hole 14 and a reflux hole 15 are provided on the pressure tube 6, wherein the liquid gap 11 is connected to the throttling hole 14 and the reflux hole 15; the isolating end cover 4 is provided with a liquid passage 16 connected to the first liquid storage chamber 7; a floating piston 17 is provided in the body 1, and the floating piston 17 is located between the end cover 2 and the isolating end cover 4; a nitrogen cavity 18 is formed between the floating piston 17 and the end cover 2; a second liquid storage chamber 19 is formed between the floating piston 17 and the isolating end cover 4; the second liquid storage chamber 19 is connected to the first liquid storage chamber 7 through the liquid passage 16.

[0020] When the piston rod 12 is hit by an external force, the piston rod 12 drives the piston 8 to move toward the isolation end cover 4, forcing the magnetorheological fluid to flow out through the throttle hole 14 arranged on the pressure tube 6 and the annular liquid gap 11 between the piston 8 and the pressure tube 6, and flow into the first liquid storage chamber 7 between the pressure tube 6 and the body 1, and then flow into the second liquid storage chamber 19 through the annular liquid passage 16 distributed on the isolation end cover 4. Driven by the magnetorheological fluid, the floating piston 17 also moves to the left, squeezing the nitrogen in the nitrogen chamber 18 for pressure accumulation. As the piston 8 gradually moves to the left, the preset throttle hole 14 is gradually closed, and the damping force increases accordingly, resulting in specific damping characteristics. When the load is removed, the accumulated pressure of the nitrogen will push the liquid through the one-way valve 5 in the middle of the isolation end cover 4, the throttle hole 14 of the inner tube, and the annular liquid gap 11 between the piston 8 and the pressure tube 6 to flow back to the pressure chamber 9, completing a working cycle. When damping adjustment is required, the wire 13 is connected to the PID control unit, and the current input to the wire 13 is adjusted by the PID control unit. The wire 13 inputs the current to the excitation coil 10 to generate a magnetic field. The excitation coil 10 generates different magnetic field strengths according to the size of the input current, which in turn affects the annular liquid gap 11 between the pressure chamber and the piston 8, causing its shape to change and slowing down its passing speed to achieve the adjustment of the damping force.

[0021] The rear end of the piston rod 12 is provided with an impact head 20 and an impact head end cover 21 , wherein the impact head 20 is provided with a through hole 22 for the wire 13 to pass through.

[0022] In order to reduce the loss of the piston rod 12, an impact head 20 is added to replace the piston rod 12 to withstand the impact. At the same time, since the wire 13 needs to be introduced from both ends of the piston rod 12, in order to avoid squeezing the wire 13 and causing the wire 13 to break when the impact head 20 is hit, a through hole 22 for leading out the wire 13 is set on the side of the impact head 20 to lead out the wire 13, so that the wire 13 comes out from the side of the impact head 20, thereby protecting the wire 13. At the same time, the impact head end cover 21 cooperates with the impact head 20 to withstand the impact.

[0023] The one-way valve 5 in the isolation end cover 4 is equipped with a return spring 23 .

[0024] When the load is removed, the accumulated pressure of the nitrogen will push the liquid back to the pressure chamber 9 through the one-way valve 5 in the middle of the isolation end cover 4, the throttling hole 14 of the inner tube, and the annular liquid gap 11 between the piston 8 and the pressure tube 6, completing a working cycle. However, during this working cycle, the one-way valve 5 is moved a certain distance by the pressure. After the working cycle is completed, the one-way valve 5 loses pressure, and the reset spring 23 pushes the one-way valve 5 to reset the pressure.

[0025] The piston 8 is provided with a notch 24 for facilitating the connection between the wire 13 and the excitation coil 10 .

[0026] The original piston 8 structure wraps the two ends of the excitation coil 10, which makes it troublesome to connect the wire 13 and the excitation coil 10. Therefore, it is necessary to adjust the original piston 8 structure to facilitate the electrical connection between the wire 13 and the excitation coil 10. Therefore, the piston 8 is provided with a notch 24 for facilitating the connection between the wire 13 and the excitation coil 10.

[0027] Compared with the prior art, the beneficial effect of the utility model is that when damping adjustment is required, the wire 13 can be connected to the PID control unit, and the damping force and current of the damper in different production modes are first calibrated, and then the current input to the wire 13 is adjusted by the preset production mode or PID control algorithm. The current is transmitted to the excitation coil 10 through the wire 13 to generate a magnetic field strength. When the magnetorheological fluid passes through the annular liquid gap 11 between the pressure tube 6 and the piston 8, the flow state changes due to the influence of the magnetic field, and the flow rate of the magnetorheological fluid passing through slows down to achieve the adjustment of the damping force. This solution can realize remote and multi-terminal damping control through the control end. The PID control unit can also be connected through the wire 13 to complete the closed loop and realize the semi-active control of the buffer.

[0028] It is obvious to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the present invention can be implemented in other specific forms without departing from the spirit or essential features of the present invention. Therefore, the embodiments should be regarded as exemplary and non-restrictive from any point of view, and the scope of the present invention is defined by the appended claims rather than the above description, and it is intended that all changes falling within the meaning and scope of the equivalent elements of the claims be included in the present invention. Any reference numeral in a claim should not be regarded as limiting the claim to which it relates.

[0029] In addition, it should be understood that although the present specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

Claims

1. A magnetorheological fluid buffer, comprising a body, end caps and guide bearings are provided at both ends of the body, characterized in that: An isolation end cover is arranged in the body, a one-way valve is arranged in the isolation end cover, a pressure tube is arranged between the isolation end cover and the guide bearing, a first liquid storage chamber is formed between the pressure tube and the body, a piston is connected in the pressure tube, a pressure chamber is formed between the pressure tube and the piston, an excitation coil is nested in the piston, a liquid gap is formed between the piston and the pressure tube, the liquid gap is communicated with the first liquid storage chamber, the piston is connected to a piston rod, the piston rod is hollow, a wire is connected in the piston rod, the wire is electrically connected to the excitation coil, a throttling hole and a reflux hole are arranged on the pressure tube, wherein the liquid gap is communicated with the throttling hole and the reflux hole, the isolation end cover is provided with a liquid passage communicated with the first liquid storage chamber, a floating piston is arranged in the body, the floating piston is located between the end cover and the isolation end cover, a nitrogen chamber is formed between the floating piston and the end cover, a second liquid storage chamber is formed between the floating piston and the isolation end cover, the second liquid storage chamber is communicated with the first liquid storage chamber through the liquid passage.

2. A magnetorheological fluid buffer according to claim 1, characterized in that: The rear end of the piston rod is provided with an impact head and an impact head end cover, wherein the impact head is provided with a through hole for the wire to pass through.

3. A magnetorheological fluid buffer according to claim 1, characterized in that: The one-way valve in the isolation end cover is equipped with a return spring.

4. A magnetorheological fluid buffer according to claim 1, characterized in that: The piston is provided with a notch for facilitating the connection between the wire and the excitation coil.

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