JP2014194253A - Damping force variable hydraulic vibration control device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a hydraulic vibration control device which gets along with a small amount of magnetic viscous fluid to be used and, moreover, can change a damping force continuously.SOLUTION: A damping force generating mechanism 25 of a hydraulic vibration control device includes a valve body 31 which is opened against a force of a spring 33 in accordance with flow of oil in two directions of a communication path 17 of oil chambers 3, 4, and an energizing force adjusting mechanism 27 which changes a valve opening pressure. A plunger 34 made of iron of the valve body 31 is received freely movably in the axial line to the energizing force adjusting mechanism 27. The energizing force adjusting mechanism 27 includes a casing 35 which air-tightly receives the plunger 34, a yoke 36 and a solenoid 37 for magnetizing the yoke which surround the outer circumference of the plunger 34, a fluid chamber 38 between the outer circumference of the plunger 34 and the yoke 36 and magnetic viscous fluid 39 filled in the fluid chamber 38. By changing electric current to the solenoid 37, viscous resistance of the magnetic viscous fluid 39 with respect to movement of the plunger 34 is increased and decreased and apparent spring force is made variable.

Description

  The present invention relates to a hydraulic vibration control device capable of changing a damping force steplessly.

  Conventionally, what was described in patent document 1 is known as a damping device which can change damping force. This vibration damping device includes a cylinder whose one end is connected to a support or a supported body, a piston that divides the inside of the cylinder into two compartments, and one end that is connected to the piston so that it can freely enter and exit in the axial direction. The end side is constituted by a supported body or a piston rod connected to the support body, a bypass pipe communicating between the two compartments of the cylinder, and a reservoir communicating with the cylinder. The cylinder and bypass pipe are filled with a magnetorheological fluid. An electromagnet is fixed to the shaft in the bypass pipe. The electromagnet forms a magnetic field in the gap with the tube and controls the flow resistance of the magnetorheological fluid flowing through the gap by changing the magnetic field, thereby changing the damping force.

JP 2001-165229 A

In the conventional vibration damping device using a magnetorheological fluid, there is a problem that the cost is high because a relatively large amount of expensive magnetorheological fluid is used.
Accordingly, an object of the present invention is to provide a hydraulic vibration control device that uses a small amount of magnetorheological fluid and that can change the damping force steplessly.

Hereinafter, the present invention will be described with reference to the accompanying drawings, but the present invention is not limited thereto.
In order to solve the above-mentioned problems, a damping force variable hydraulic vibration damping device of the present invention includes a cylinder 1 in which hydraulic oil is sealed, a slidably fitted in the cylinder 1 and two oil chambers 3 in the cylinder 1. , 4, a piston rod 5 having one end connected to the piston 2 and the other end extending to the outside of the cylinder 1, and an electromagnetic as a damping force generating mechanism that generates a damping force by communicating between the two oil chambers. And a valve device 25. The solenoid valve device 25 is provided with a bypass pipe 17 which is a communication path communicating with the oil chambers 3 and 4, and is opened against the force of the spring 33 by a one-way oil flow provided in the bypass pipe 17, thereby damping force. A first valve body 31 that generates a valve, a second valve body 31 that opens against the force of the spring 33 due to the flow of oil in the other direction and generates a damping force, and the valve bodies 31 that open. And an urging force adjusting mechanism 27 for changing the pressure. The urging force adjusting mechanism 27 includes an iron plunger 34 extending from the valve body 31 in the operation axis direction thereof, a casing 35 that receives the plunger 34 in an airtight manner, and an outer periphery of the plunger 34 enclosed in the casing 35. A yoke 36 provided, a solenoid 37 for magnetizing the yoke, a fluid chamber 38 formed between the outer periphery of the plunger 34 and the yoke 36, and a magnetorheological fluid 39 filled in the fluid chamber 38 are provided. . By changing the current flowing to the solenoid 37, the viscous resistance of the magnetorheological fluid with respect to the movement of the plunger 34 is increased or decreased to make the apparent spring force variable.

  The present invention provides an inexpensive hydraulic damping device capable of changing a damping force steplessly using a small amount of a magnetorheological fluid.

It is sectional drawing of the hydraulic damping device which concerns on this invention. It is II-II arrow sectional drawing in FIG. It is a side view of the hydraulic damping device of FIG. FIG. 2 is an enlarged sectional view of a part of the hydraulic vibration control device of FIG. 1.

Embodiments of the present invention will be described with reference to the drawings.
In FIG. 1, a piston 2 is slidably inserted into a cylinder tube 1, and the cylinder tube 1 is partitioned into first and second oil chambers 3 and 4. The piston rod 5 extends on both sides of the piston 2 and passes through the cylinder covers 6 and 7 at both ends of the cylinder tube 1 in an airtight manner. A load column 8 is connected to the cylinder cover 6 on one end side, and a puller 9 for connecting to a support body or a supported body is provided at the tip thereof. One end side of the piston rod 5 extends into the load column 8, the other end side extends through the cylinder cover 7 and extends outward, and at the tip thereof, a puller for connecting to a supported body or a support body 10 is provided.

  The cylinder covers 6 and 7 communicate with each other through oil passages 11, 12, 13 and 14, valve cases 15 and 16, and a bypass pipe 17, respectively.

  The cylinder covers 6 and 7 have a valve case 15 communicating with the oil chambers 3 and 4 via the oil passages 11 and 12, respectively, and a valve case 16 communicating with the oil chambers 3 and 4 via the oil passages 13 and 14, respectively. Is fixed. The valve cases 15 and 16 communicate with each other via an oil passage 18.

  A check valve 19 is provided in the valve case 15. The check valve 19 always opens the flow path between the oil chambers 3 and 4, but when the oil pressure in the oil chambers 3 and 4 increases, the bypass pipe 17 closes the flow path and passes through the valve case 16. Stop the distribution of oil to

  An accumulator 20 for absorbing a change in the capacity of the hydraulic oil due to heat is provided at an intermediate portion of the bypass pipe 17. The accumulator 20 includes a reservoir tube 22 communicating with the bypass pipe 17 through an oil passage 21, a free piston 23 inserted into the reservoir tube 22, and a spring 24. The spring 24 constantly applies pressure to the free piston 23. The above is the configuration of the vibration damping device main body.

  An electromagnetic valve device 25 that is a damping force generator is assembled to the valve case 16. The electromagnetic valve device 25 includes a valve mechanism 26 provided in the valve case 16 and an urging force adjusting mechanism 27 attached to the outside of the valve case 16.

  The valve case 16 communicates with the oil chambers 3 and 4 through the oil passages 13 and 14, the valve case 15 through the oil passage 18, and the bypass pipe 17 through the oil passage 28. An inner case 29 that holds the valve seat 30 on one end side is inserted into the valve case 16. The inner case 29 is internally provided with a valve body 31. The valve seat 30 is interposed in the oil passages 13 and 14, and the valve body 31 opens and closes the oil passages 13 and 14.

  An urging force adjusting mechanism 27 is fixed to the valve case 16 via a connection flange 32. The valve body 31 is coupled to one end of a magnetic plunger 34 that passes through the biasing force adjusting mechanism 27 so as to be movable in the axial direction, and is biased against the valve seat 30 by a spring 33 via the plunger 34. The valve body 31 and the plunger 34 are screwed together so as to be separable from each other.

  The biasing force adjusting mechanism 27 includes a magnetic casing 35 that receives the plunger 34 in an airtight manner, a yoke 36 that is provided in the casing 35 so as to surround the outer periphery of the plunger 34, and a solenoid 37 that magnetizes the yoke 36. . A fluid chamber 38 is formed between the outer periphery of the plunger 34 and the yoke 36, and the fluid chamber 38 is filled with a magnetorheological fluid 39. When a current is passed through the solenoid 37, a magnetic field passing through the yoke 36, the casing 35, the magnetorheological fluid 39, and the plunger 34 is generated. Form. When the plunger 34 moves with respect to the casing 35, the shear stress of the magnetic powder cluster becomes viscous resistance and generates a load in a direction that prevents the movement of the plunger 34. By changing the current flowing to the solenoid 37, the viscosity of the magnetorheological fluid 39 can be changed, and the resistance to movement of the plunger 34 can be increased or decreased. Thereby, the apparent spring force is changed.

  The casing 35 is hermetically closed at both ends by casing covers 40 and 41 and rod covers 42 and 43 that are airtightly fixed to the outside of the casing covers 40 and 41. The rod cover 42 on one end side is connected to the valve case 26 via the connection flange 32. The casing covers 40 and 41 have oil supply ports 40a and 41a for supplying a magnetorheological fluid, respectively. The oil filler ports 40a and 41a are closed by steel balls 40b and 41b and bolts 40c and 41c.

  The plunger 34 passes through the rod cover 42 and the casing cover 40 on one end side so as to be movable in the axial direction, passes through the casing 35, and passes through the casing cover 41 and the rod cover 43 on the other end side so as to be movable in the axial direction. And protrudes into the spring receiving tube 44. A retaining member 45 that also serves as a spring seat is fixed to the other end of the plunger 34 that protrudes into the spring receiving tube 44.

  The spring receiving tube 44 has a threaded portion 44a on the inner periphery, and a spring receiving disk 46 and a rotation-stopping disk 47 are screwed into this, and are connected by bolts 48 with a space between each other. A spring 33 is inserted between the spring receiving seat 45 and the spring receiving disk 46.

When a support body (not shown) and a supported body are relatively displaced in the axial direction of the cylinder 8, the piston 2 slides and hydraulic oil flows into the oil passage 11 (12). As a result, the check valve 19 lifts and closes the oil passage. The hydraulic oil flows into the oil passage 13 (14), displaces the valve body 31, and flows to the bypass pipe 17 through the electromagnetic valve device 25. At this time, a pressure difference is generated between the oil chambers 3 and 4 due to the relationship between the oil amount and the flow path cross-sectional area, and a damping force is generated that suppresses the relative displacement between the support and the supported body. Although this damping force depends on the spring force of the spring 33 that biases the valve body 31, the spring force can be apparently changed by the biasing force adjusting mechanism 5. That is, the viscosity of the magnetorheological fluid 39 is changed by changing the current flowing to the solenoid 37, and the resistance against the movement of the valve body 31 is changed through the plunger 34. When the current to the solenoid 37 is increased to change the direction of increasing the viscosity of the magnetorheological fluid 39, the amount of movement of the valve element 31 decreases and the cross-sectional area of the flow path decreases, resulting in a larger pressure difference. Born and gains great damping force.
When the viscous resistance of the magnetorheological fluid 39 changed by the biasing force adjusting mechanism 5 is added to the spring force of the biasing spring 33, the spring force apparently changes. Thereby, the damping force can be changed steplessly. The amount of magnetorheological fluid used in the solenoid valve device 25 is about several tens of cc, and the amount of magnetorheological fluid used is much smaller than that of a damper using a conventional magnetorheological fluid. As a result, the price can be reduced.

  If the connection flange 32 is removed from the valve case 16, the inner case 29 and the urging force adjusting mechanism 27 can be easily removed and disassembled. Therefore, replacement to the valve seat 30 having a different hole shape, replacement of the valve body 31, adjustment of the spring 33, and the like can be easily performed. The present invention can be applied not only to an oil damper but also to a hydraulic vibration isolator.

DESCRIPTION OF SYMBOLS 1 Cylinder tube 2 Piston 3 1st oil chamber 4 2nd oil chamber 5 Piston rod 6 Cylinder cover 7 Cylinder cover 8 Load column 9 Puller 10 Puller 11 Oil passage 12 Oil passage 13 Oil passage 14 Oil passage 15 Valve case 16 Valve Case 17 Bypass pipe 18 Oil passage 19 Check valve 20 Accumulator 21 Oil passage 22 Reservoir tube 23 Free piston 24 Spring 25 Electromagnetic valve device 26 Valve mechanism 27 Energizing force adjustment mechanism 28 Oil passage 29 Inner case 30 Valve seat 31 Valve body 32 Connection Flange 33 Spring 34 Plunger 35 Casing 36 Yoke 37 Solenoid 38 Fluid chamber 39 Magnetorheological fluid 40 Casing cover 40a Filling port 40b Steel ball 40c Bolt 41 Casing cover 41a Filling port 41b Steel ball 41c Bolt 42 Rod cover 43 Rod cover 44 Receiving cylinder 45 spring seat 46 spring receiving disc 47 anti-rotation disc

Claims (4)

A cylinder filled with hydraulic oil, and a piston that is slidably fitted in the cylinder and divides the cylinder into two oil chambers;
A piston rod having one end connected to the piston and the other end extended to the outside of the cylinder;
A damping force generating mechanism that communicates between the two oil chambers and generates a damping force;
The damping force generation mechanism opens a valve against a spring force by a communication path that communicates between one oil chamber and the other oil chamber in the cylinder and a flow of oil in one direction provided in the communication path. The first valve body that generates a damping force, the second valve body that opens against the spring force by the flow of oil in the other direction, and generates a damping force, and the valve opening pressure of each of these valve bodies is changed. An urging force adjusting mechanism to be
The urging force adjusting mechanism includes an iron plunger extending from the valve body in an operation axis direction thereof, a casing for receiving the plunger in an airtight manner, a yoke provided in the casing so as to surround an outer periphery of the plunger, and a A solenoid for magnetizing the yoke, a fluid chamber formed between the outer periphery of the plunger and the yoke, and a magnetorheological fluid filled in the fluid chamber;
A damping force variable hydraulic damping device, wherein the apparent spring force is variable by increasing / decreasing the viscous resistance to the movement of the plunger by changing the current flowing to the solenoid. The plunger penetrates the casing of the biasing force adjusting mechanism in an airtight manner, and the other end protrudes from the casing.
On the outside of the casing, a spring receiving portion for receiving the other end side of the plunger is provided,
The damping force variable hydraulic damping device according to claim 1, wherein a spring that presses the other end of the plunger toward one end side is provided in the spring receiving portion. The spring receiving portion includes a cylindrical spring receiving tube that is concentrically fixed to the plunger on the outside of the casing, and a spring seat that is screwed to the spring receiving tube so as to be movable forward and backward in the axial direction.
3. The damping force variable hydraulic damping device according to claim 2, wherein an initial deflection amount of the spring can be adjusted by adjusting a forward / backward movement of the spring seat. The casing of the biasing force adjusting mechanism includes a rod cover that allows the plunger to pass through in an airtight manner on one end side,
The valve body and the valve seat are provided in a cylindrical inner case that is removably fitted inside a cylindrical valve case that is fixed to the apparatus body.
The valve seat is detachably connected to the inner end of the inner case on the device main body side,
The valve body is detachably connected to one end of the plunger protruding into the inner case,
The damping force variable hydraulic damper according to claim 1, wherein the rod cover is detachably connected to an outer end of the inner case.

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