JP2015081639A - Shock absorber - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable a shock absorber to generate electricity without causing the same to increase in size.SOLUTION: A shock absorber comprises: a cylinder 54 with conductive fluid sealed therein; a piston 55 which separates the cylinder into a first fluid chamber 61 and a second fluid chamber 62; flow passages 71 and 72 which are installed in the piston with overall lengths longer than the length along a moving direction of the piston and enables the conductive fluid to flow between the first fluid chamber and the second fluid chamber; magnets 73a, 74a and 74c which are installed on side walls of the flow passages in the piston; and electrodes 75a, 75c and 76c which are installed on the side walls of the flow passages so as to face in a direction perpendicular to the direction that magnetic flux generated by the magnets in the piston extends and extract electricity generated when the conductive fluid passes through the flow passages along with motion of the piston with respect to the cylinder.

Description

  The present invention relates to a shock absorber that generates power using vibration applied to itself.

  The shock absorber that constitutes a part of the suspension device buffers the shock by the flow resistance of the hydraulic fluid that is generated as the piston slides in the cylinder. Specifically, the shock absorber includes a cylinder filled with hydraulic fluid, a piston in which a plurality of orifices are formed to partition the inside of the cylinder into two fluid chambers, and a piston rod that transmits external force to the piston. Consists of the subject.

  In the shock absorber, the piston slides in the cylinder due to an increase in the load applied to the wheel, and the volumes of the two fluid chambers increase / decrease as the cylinder moves relative to the cylinder. As a result, the hydraulic fluid filled in the two fluid chambers in the cylinder moves in the direction opposite to the sliding direction of the piston. And resistance to movement of a piston arises by resistance at the time of hydraulic fluid circulating through each orifice. The shock is buffered by the damping force generated at this time.

  By the way, a power generation device that generates power using vibration energy applied to the shock absorber when the vehicle travels has been considered. The power generation device described in Patent Document 1 below is obtained by attaching a giant magnetostrictive material and a coil to the outer periphery of a piston rod located in a cylinder of a shock absorber. When a vehicle equipped with this shock absorber travels, a load is applied to the piston rod due to vibrations transmitted from the wheels when the vehicle travels, and the piston rod is distorted in the compression direction or the tensile direction, and the giant magnetostriction provided in the piston rod is also applied. The material will also be distorted. A dielectric electromotive force is generated in the coil using a magnetic field generated in the coil due to distortion of the giant magnetostrictive material, the electric power is stored, and the electric power is supplied to various parts of the vehicle as an auxiliary battery of the vehicle.

  However, in order to adopt such a power generation device, a power generation mechanism composed of a giant magnetostrictive material and a coil is created separately from a mechanism (cylinder and piston that encloses hydraulic fluid) that exhibits the original function of the shock absorber. However, there is a problem that the shock absorber becomes large.

JP 2005-102445 A

  An object of the present invention is to enable power generation while suppressing an increase in the size of a shock absorber.

  In the present invention, a cylinder in which a conductive fluid is enclosed, a piston that partitions the cylinder into a first fluid chamber and a second fluid chamber, and a total length that is longer than a length dimension along the moving direction of the piston A flow path that is provided in the piston and that allows the conductive fluid to flow between the first fluid chamber and the second fluid chamber, and is provided on a side surface of the flow path in the piston. The conductive fluid is provided on a side surface of the flow path so as to face a magnet and a direction in which the magnetic flux formed by the magnet extends in the piston, and the piston moves relative to the cylinder. And an electrode for taking out a current flowing when passing through the flow path.

  Here, the “conductive fluid” indicates a highly dispersed low melting point alloy or metal nanoparticles having conductivity such as a liquid metal, for example.

  The “flow path” refers to, for example, a choke that generates a damping force by applying resistance to the fluid depending on the length of the passage, and an orifice that generates a damping force by applying resistance to the fluid by the cross-sectional area of the passage. It is a concept that includes.

  The piston includes a plurality of flow paths, and one flow path allows the conductive fluid to flow from the first fluid chamber to the second fluid chamber, and the conductive And a first restricting means for prohibiting the flow of the conductive fluid from the second fluid chamber to the first fluid chamber, and the other flow path is configured such that the conductive fluid is the second fluid chamber. A second restricting means for allowing the fluid to flow from the fluid chamber to the first fluid chamber and prohibiting the conductive fluid from flowing from the first fluid chamber to the second fluid chamber; It is preferable.

  ADVANTAGE OF THE INVENTION According to this invention, electric power generation is enabled, suppressing the enlargement of a shock absorber.

1 is a schematic cross-sectional view showing a suspension device according to an embodiment of the present invention. The plane sectional view showing the piston and piston rod in the embodiment. XX sectional drawing in FIG. Schematic which shows the principle of MHD electric power generation in the embodiment. Operation | movement explanatory drawing of the shock absorber of the embodiment. Operation | movement explanatory drawing of the shock absorber of the embodiment. FIG. 4 is a view corresponding to FIG. 3 of a shock absorber according to a modification of the present invention. FIG. 3 is a view corresponding to FIG. 3 of a conventional shock absorber.

  An embodiment of the present invention will be described with reference to the drawings.

  The shock absorber 52 for a vehicle capable of generating electric power according to the present embodiment constitutes a part of the suspension device 5. FIG. 1 schematically shows the suspension device 5.

  The suspension device 5 is mainly composed of a spring 51 and a shock absorber 52 disposed inside the spring 51. The upper part of the suspension device 5 is connected to the upper support 56. More specifically, the upper support 56 is used to attach the upper end of the piston rod 53 of the shock absorber 52 and the upper end of the spring 51 to a vehicle body (not shown).

  The spring 51 is, for example, a compression coil spring 51, and is supported by an upper bracket 57 of an upper support 56 attached to the vehicle body at an upper end portion and a lower bracket 58 attached to an outer cylinder of the shock absorber 52 at the lower end portion. It is supported. In other words, the spring 51 is sandwiched between the upper bracket 57 and the lower bracket 58 and is arranged around the piston rod 53, supports the weight of the vehicle body, and impacts from the road surface, that is, a tire (not shown) and Reduce and mitigate vibrations transmitted from the wheel to the vehicle body via the knuckle.

  The shock absorber 52 has a lower portion connected to a support member (not shown) that supports the wheel, and an upper end portion of the piston rod 53 is fixedly attached to the vehicle body. It is intended to attenuate the vertical vibrations. That is, when an external force in the vertical direction acts on the wheel from the road surface, the distance between the connection point at the lower end portion of the shock absorber 52 and the upper end portion of the piston rod 53 extends in the axial direction that coincides with the central axis of the shock absorber 52. Compress.

  More specifically, the shock absorber 52 includes a cylinder 54 in which a conductive fluid is sealed, a piston 55 that partitions the cylinder 54 into a first fluid chamber 61 and a second fluid chamber 62, A flow which is provided in the piston 55 and has a total length longer than the length dimension along the moving direction and which allows the conductive fluid to flow between the first fluid chamber 61 and the second fluid chamber 62. A pair of magnets (73a and 74a, 73b and 74b, 73c and 74c, 73d and 74d) provided on the side surfaces of the flow paths 71 and 72 in the piston 55, and the pair in the piston 55. Of magnets (73a and 74a, 73b and 74b, 73c and 74c, 73d and 74d) are provided on the side surfaces of the flow paths 71 and 72 so as to cross each other. A pair of electrodes (75a and 76a, 75b and 76b, 75c and 76c, 75d) for taking out the current that flows when the conductive fluid passes through the flow paths 71 and 72 as the stone 55 moves relative to the cylinder 54. 76 d) and a piston rod 53 connected to the piston 55.

  The cylinder 54 has a cylindrical shape and is filled with a conductive fluid. The conductive fluid is a low melting point alloy having conductivity such as a liquid metal or a metal nanoparticle that is highly dispersed in a solution. Specific examples include Galinstan, NaK, U-Alloy, and the like. A liquid metal is mentioned. Galinstan is an alloy made of gallium (Ga), indium (In), and tin (Sn). NaK (sodium potassium alloy) is an alloy composed of sodium (Na) and potassium (K). U-Alloy is an alloy made of bismuth (Bi), indium (In), tin (Sn), cadmium (Cd), and lead (Pb). In addition, if these liquid metals are in contact with other solid metals, they may penetrate into the metals and cause embrittlement, which may reduce the strength of the metals. It is preferable to appropriately coat the metal portions such as the cylinder 54, the piston 55, and the piston rod 53 that come into contact with the fluid. Further, a piston 55 schematically shown in FIGS. 2 and 3 is inserted into the cylinder 54 so as to be slidable in the vertical direction.

  The piston 55 is arranged to be movable in the longitudinal direction within the cylinder 54 and is fixed to the lower end portion of the piston rod 53. The piston 55 defines the inside of the cylinder 54. In the cylinder 54, a first fluid chamber 61 is formed on the wheel side, and a second fluid chamber 62 is formed on the upper support 56 side. . The piston 55 is formed with a first flow path 71 and a second flow path 72 that penetrate in the axial direction from one end face to the other end face and communicate with the first fluid chamber 61 and the second fluid chamber 62. ing. In the present embodiment, two each of the first flow path 71 and the second flow path 72 are provided, but the arrangement and number thereof may be appropriately selected according to the required damping force characteristics. Good.

  Each of the flow paths 71 and 72 has a substantially quadrangular cross section, and communicates the first fluid chamber 61 and the second fluid chamber 62 in a non-linear manner, specifically in a spiral shape. More specifically, each flow path 71, 72 has a straight line shape along the moving direction of the piston 55 at both ends 71 a, 71 b, 72 a, 72 b facing the first fluid chamber 61 or the second fluid chamber 62. The intermediate portions 71c, 72c sandwiched between the both end portions 71a, 71b, 72a, 72b are formed in a spiral shape having a circular shape in plan view, and the total length of each flow path 71, 72 is the thickness dimension of the piston 55, That is, it is set to be longer than the length dimension L along the moving direction of the piston 55. Each flow path 71 and 72 plays the role of the orifice which adjusts flow volume by changing the cross-sectional area of a channel | path, and provides resistance corresponding to a cross-sectional area to an electroconductive fluid.

  One flow path (two first flow paths 71) allows the conductive fluid to flow from the first fluid chamber 61 to the second fluid chamber 62, and the conductive fluid flows. A first restricting means 77 for prohibiting the flow from the second fluid chamber 62 to the first fluid chamber 61 is provided. The first restricting means 77 is a valve that controls the conductive fluid to flow from the first fluid chamber 61 to the second fluid chamber 62 only when the shock absorber 52 is compressed. The other flow path (two second flow paths 72) allows the conductive fluid to flow from the second fluid chamber 62 to the first fluid chamber 61, and allows the conductive fluid to flow. A second restricting means 78 for prohibiting the flow from the first fluid chamber 61 to the second fluid chamber 62 is provided. The second regulating means 78 is a valve that controls the conductive fluid to flow from the second fluid chamber 62 to the first fluid chamber 61 only when the shock absorber 52 is extended.

  A pair of magnets 73a, 73b, 73c, 73d, 74a, 74b, 74c, 74d are attached to the inner peripheral surface of each flow path 71, 72. N poles 73a, 73b, 73c, 73d and S poles 74a, 74b, 74c, and 74d are provided so as to face each other with the internal space of the flow paths 71 and 72 interposed therebetween. In the present embodiment, the N poles 73a, 73b, 73c, 73d of the magnet and the S poles 74a, 74b, 74c, 74d are arranged in parallel.

  A pair of electrodes 75a, 75b, 75c, 75d, 76a, 76b, 76c, and 76d are attached to the inner peripheral surface of each of the flow paths 71 and 72. The + poles 75a, 75b, 75c, and 75d and the-pole 76a, 76b, 76c, and 76d are provided so as to face each other with the internal space of the flow paths 71 and 72 interposed therebetween. Here, the negative electrodes 76a, 76b, 76c, and 76d are electrodes that extract electrons from the conductive fluid. The negative electrode 76a and the negative electrode 76b are connected, and the negative electrode 76c and the negative electrode 76d are connected. Has been. On the other hand, the + poles 75a, 75b, 75c, and 75d are electrodes that emit electrons into the conductive fluid. The + pole 75a and the + pole 75b are connected, and the + pole 75c and the + pole 75d are connected. Connected. The pair of electrodes (75a and 76a, 75b and 76b, 75c and 76c, 75d and 75d) are insulated by the magnets 73a, 73b, 73c, 73d, 74a, 74b, 74c, and 74d, respectively.

  In the present embodiment, the positive poles 75a, 75b, 75c, and 75d of the electrode and the negative poles 76a, 76b, 76c, and 76d are the N poles 73a, 73b, 73c, and 73d of the magnet and the S poles 74a, 74b, 74c, and 74d. Are arranged at right angles to each other. That is, the lines connecting the + poles 75a, 75b, 75c, and 75d of the electrode and the -poles 76a, 76b, 76c, and 76d are the N poles 73a, 73b, 73c, and 73d of the magnet and the S poles 74a, 74b, 74c, and 74d. Is perpendicular to the line connecting the two. Each electrode 75a, 75b, 75c, 75d, 76a, 76b, 76c, 76d is an auxiliary battery that is an electric storage means for storing the induced electromotive force generated by the movement in the flow paths 71, 72 of the conductive fluid. A cable (not shown) is connected to an external load resistor such as various electric devices mounted on the vehicle.

  The piston rod 53 is connected to the piston 55 and extends in the longitudinal direction of the cylinder 54, and transmits an external force to the piston 55. The piston rod 53 is formed in a hollow pipe shape, and a cable connected to the electrodes 75a, 75b, 75c, 75d, 76a, 76b, 76c, and 76d is disposed therein. This cable is drawn from the upper end of the piston rod 53 to the outside of the piston rod 53.

  The shock absorber 52 absorbs this increasing / decreasing volume because the volume of the piston rod 53 located inside the cylinder 54 increases / decreases as the piston 55 slides relative to the cylinder 54. A gas chamber 63 filled with nitrogen is provided.

  In the suspension device 5 configured as described above, when the vehicle travels and the vehicle body side and the wheel side are relatively displaced due to the unevenness of the road surface, the spiral spring 51 located outside the shock absorber 52 is The vehicle body side and the wheel side relatively vibrate due to expansion and contraction, and the piston 55 slides in the cylinder 54. At that time, when the conductive fluid flows through the flow paths 71 and 72 provided in the piston 55 by the movement of the piston 55, a damper action is performed and an induced electromotive force generates MHD (Magneto-Hydro-Dynamics) power generation. The action is carried out.

  FIG. 4 schematically shows the principle of MHD power generation. For example, when a fluid such as a conductive fluid indicated by a white arrow moves in the magnetic field B formed between the pair of electrodes 75 and 76 at a flow velocity u, a current (electromotive force u × B) is generated between the electrodes 75 and 76. Occur. That is, when the fluid moves in the magnetic field B from the near side to the far side in the figure, electrons (charges -e) in the fluid receive a Lorentz force toward the left side in the figure. As a result, one electrode 76 becomes negative due to excessive electrons, and the other electrode 75 is positively charged. This current is supplied to the external load resistor 70 and the like through the cable 79 connected to the electrodes 75 and 76. Note that the viscosity of the conductive fluid of the present embodiment is set sufficiently smaller than the Lorentz force generated by the structure of the shock absorber 52 of the present embodiment. This is because the resistance to the piston movement of the fluid increases in proportion to the lengths of the flow paths 71 and 72. Therefore, in order to achieve both the power generation by the shock absorber 52 and the damping force control, the fluid viscosity resistance is set to the Lorentz force, That is, it is necessary to make it sufficiently smaller than the repulsive force generated by the electromagnetic force.

  Hereinafter, the case where the shock absorber 52 according to the present embodiment operates in the extending direction will be described with reference to FIG. In FIG. 5, the relative flow of the conductive fluid with respect to the piston 55 is indicated by white arrows.

  First, the piston rod 53 starts to operate in the direction of arrow A from the state where the first fluid chamber 61 and the second fluid chamber 62 have substantially the same pressure. The piston 55 reduces the volume of the second fluid chamber 62 and increases the volume of the first fluid chamber 61 with the relative movement with respect to the cylinder 54. Therefore, the pressure in the second fluid chamber 62 is relatively higher than the pressure in the first fluid chamber 61. The second fluid chamber 62 is in a state where the first restricting means 77 closes the first flow path 71 and the second restricting means 78 opens the second flow path 72. The electrically conductive fluid present in the fluid moves mainly to the first fluid chamber 61 via the second flow path 72. At this time, since the second flow path 72 functions as a so-called orifice that narrows the passage through which the conductive fluid flows, a large resistance is generated when the conductive fluid moves through the second flow path 72.

  In addition, the conductive fluid moves in a magnetic field formed between a pair of magnets (73c and 74c, 73d and 74d) attached to face the inner peripheral surface of the second flow path 72, and a current (electromotive force) is generated. ) Occurs. This electric current is supplied to various electric devices (external load resistance), an auxiliary battery, and the like mounted on the vehicle through a cable arranged inside the piston rod 53.

  Next, the case where the shock absorber 52 according to the present embodiment operates in the contracting direction will be described with reference to FIG. The damping force characteristic of the shock absorber 52 according to the present embodiment is the same as that in the extension direction. In FIG. 6, similarly to FIG. 5, the relative flow of the conductive fluid with respect to the piston 55 is indicated by a white arrow.

  The piston rod 53 starts to operate in the direction of arrow B from the state where the first fluid chamber 61 and the second fluid chamber 62 have substantially the same pressure. The piston 55 reduces the volume of the first fluid chamber 61 and increases the volume of the second fluid chamber 62 with the relative movement with respect to the cylinder 54. Therefore, the pressure in the first fluid chamber 61 is relatively higher than the pressure in the second fluid chamber 62. The first fluid chamber 61 is in a state where the first restricting means 77 opens the first flow path 71 and the second restricting means 78 closes the second flow path 72. The electrically conductive fluid present in the fluid moves mainly to the second fluid chamber 62 via the first flow path 71. At that time, the first flow path 71 functions as a so-called orifice that narrows the passage through which the conductive fluid flows, so that a large resistance is generated when the conductive fluid moves through the first flow path 71.

  In addition, the conductive fluid moves in a magnetic field formed between a pair of magnets (73a and 74a, 73b and 74b) attached to face the inner peripheral surface of the first flow path 71, and a current (electromotive force) ) Occurs. This electric current is supplied to various electric devices (external load resistance), an auxiliary battery, and the like mounted on the vehicle through a cable arranged inside the piston rod 53.

  In this embodiment, a cylinder 54 in which a conductive fluid is enclosed, a piston 55 that partitions the cylinder 54 into a first fluid chamber 61 and a second fluid chamber 62, and a movement direction of the piston 55 are arranged. Flow paths 71 and 72 that are provided in the piston 55 and have a total length longer than the length dimension L and allow the conductive fluid to flow between the first fluid chamber 61 and the second fluid chamber 62. A pair of magnets (73a and 74a, 73b and 74b, 73c and 74c, 73d and 74d) provided on side surfaces of the flow paths 71 and 72 in the piston 55, and a pair of magnets (73a and 73d in the piston 55). 74a, 73b and 74b, 73c and 74c, 73d and 74d) are provided on the side surfaces of the flow paths 71 and 72 so as to face the direction in which the magnetic flux extends. A pair of electrodes (75a and 76a, 75b and 76b, 75c and 76c, 75d) for taking out the current that flows when the conductive fluid passes through the flow paths 71 and 72 as the stone 55 moves relative to the cylinder 54. And 76d), a shock absorber 52 is provided.

  According to the present embodiment, the Faraday is maintained while the damper function as the shock absorber 52 is maintained by enclosing the conductive fluid in place of the hydraulic fluid in the space where the hydraulic fluid for shock buffering has been enclosed. It is possible to add a power generation function capable of obtaining power based on the electromagnetic induction law. Therefore, the electric power generated by the shock absorber 52 can be used as a power source for vehicle electrical equipment.

  In the vehicle shock absorber 52, a relatively large repetitive load is constantly applied to the piston rod 53 as long as the vehicle is traveling. Therefore, it is possible to secure a sufficient amount of power generation and efficiently store power in the auxiliary battery, or to stably supply power to various parts of the vehicle. Thus, since the energy recovered during the traveling of the vehicle can be released at the time of starting or during the traveling, if the shock absorber 52 is applied to a vehicle equipped with the internal combustion engine, the driving force is generated from the crankshaft of the internal combustion engine. It is possible to reduce the amount of power generated by the rotation of the alternator in response to this transmission. That is, since the energy that should be generated by the internal combustion engine that is the drive source can be reduced, fuel efficiency can be improved.

  In particular, since the shock absorber 52 of the present embodiment employs a spiral structure as the shape of each of the flow paths 71 and 72, the flow path 71 is within the same thickness dimension of the piston 55 as compared with the linear flow path. , 72 can be lengthened. Therefore, the power generation output can be improved by increasing the volume of the conductive fluid flowing in the passages 71 and 72 without increasing the thickness dimension of the piston 55.

  That is, as a method of increasing the volume of the conductive fluid flowing in the passages 71 and 72 in order to improve the power generation output of the shock absorber 52, the conventional linear flow paths 71 and 72 as shown in FIG. It is possible to consider a method of lengthening without changing the size. However, the thickness dimension L of the piston 55 increases, and the suspension device itself increases in size. In order to increase the volume of the conductive fluid flowing in the passages 71 and 72, a method of increasing the diameters of the flow paths 71 and 72 is also conceivable. Although this also improves the power generation output, there is a problem that the fluid velocity of the fluid flowing in the passages 71 and 72 changes, and the original damper function of the shock absorber 52 does not work effectively.

  However, by making the part that performs MHD power generation into a spiral structure as in this embodiment, the diameter of the flow paths 71 and 72 is changed without changing the conventional structure such as the cylinder 54 other than the piston 55. Without changing the fluid velocity of the conductive fluid, the volume of the portion that performs MHD power generation and the volume of the conductive fluid that passes through the portion that performs MHD power generation can be increased. Can be increased.

  Further, since the basic structure other than the piston 55 of the normal shock absorber 52 can be used as it is, it is smaller and less expensive than the conventional power generator in which the giant magnetostrictive material and the coil are arranged in the shock absorber as described above. A power generation device can be realized. Moreover, the amount of power generation can be increased as compared with the conventional one.

  Since the conductive fluid is sealed in the cylinder 54 instead of the hydraulic fluid, the damper function of the shock absorber 52 is not lost even if the power generation device fails due to, for example, a cable disconnection.

  Furthermore, the piston 55 of the present embodiment includes a plurality of flow paths 71 and 72, and one of the flow paths 71 causes the conductive fluid to flow from the first fluid chamber 61 to the second fluid chamber 62. The first restricting means 77 that allows the flow of the conductive fluid and prohibits the conductive fluid from flowing from the second fluid chamber 62 to the first fluid chamber 61 is provided. The flow path 72 allows the conductive fluid to flow from the second fluid chamber 62 to the first fluid chamber 61, and the conductive fluid flows from the first fluid chamber 61 to the second fluid chamber 61. Since the second restricting means 78 that prohibits the flow to the fluid chamber 62 is provided, a rectifier circuit that takes into account the direction of the current that changes in accordance with the change in the direction of the flow of the conductive fluid becomes unnecessary. Therefore, realizing the power generation device at a relatively low cost It can be.

  Also, if the cable connected to the electrodes 75a, 75b, 75c, 75d, 76a, 76b, 76c, and 76d is connected to a variable resistor, the generated current is controlled by changing the resistance value of the variable resistor to The damping force of the absorber 52 can also be controlled. Instead of the variable resistor, a switch that can switch ON / OFF the circuit connected to the electrodes 75a, 75b, 75c, 75d, 76a, 76b, 76c, and 76d may be used.

  Furthermore, the damping force characteristic of the shock absorber 52 may be changed by applying a voltage or current from the outside.

  The present invention is not limited to the embodiment described in detail above.

  For example, the flow path may not be provided with a regulating means for regulating the flow of the conductive fluid. In this case, the flow path includes a first flow in which a conductive fluid flows relative to the piston from the first fluid chamber to the second fluid chamber as the piston moves, and a piston in a direction opposite to the first flow. Moves both from the second fluid chamber to the first fluid chamber and a second flow of conductive fluid relative to the piston. The direction of the current that can be extracted from the electrode changes between the first flow and the second flow. Therefore, in this case, a rectifier circuit may be connected between the electrode and the battery or the external load resistor to make the direction of the current flowing through the battery or the external load resistor constant. In this case, one channel may be used.

  Each flow path may have any shape as long as it has a total length longer than the length dimension along the moving direction of the piston, and is not limited to the illustrated one, and can be variously changed. For example, the flow path of the shock absorber according to the modification of the present invention shown in FIG. 7 has a substantially square cross section, and the first fluid chamber and the second fluid chamber are non-linearly defined. It communicates like a pleat. Hereinafter, the same reference numerals are given to the same or corresponding parts as those of the above-described embodiment, and detailed description thereof will be omitted. In each of the flow paths 71 and 72 according to this modification, both end portions 71a, 71b, 72a, and 72b facing the first fluid chamber or the second fluid chamber are linear along the moving direction of the piston 55. In addition, the intermediate portions 71c and 72c sandwiched between the both end portions 71a, 71b, 72a and 72b are formed in a pleated shape having a bent shape when viewed from the front, and the total length of each flow path 71 and 72 is the thickness dimension of the piston 55, that is, the piston 55 is set to be longer than the length L along the moving direction. If it is such, the effect according to embodiment mentioned above can be acquired.

  Furthermore, the flow path is not limited to the hole-shaped one drilled in the piston, and can be variously changed, for example, including a notch portion in the outer circumferential direction and constituting the flow path in cooperation with the inner wall of the cylinder. .

  Also, the piston is not limited to a pair of magnets provided that at least one magnet for forming a magnetic flux is provided. Furthermore, the piston is not limited to the one provided with a pair of electrodes, and any piston may be used as long as at least one electrode for taking out electrons in the fluid subjected to the Lorentz force is provided.

  In addition, the specific configuration of each unit, the processing procedure, and the like can be variously modified without departing from the spirit of the present invention.

  The present invention can be used for a shock absorber mounted on a vehicle.

52 ... Shock absorber 54 ... Cylinder 55 ... Piston L ... Length dimension 61 ... First fluid chamber 62 ... Second fluid chamber 71, 72 ... Channel 73, 73a, 73b, 73c, 73d, 74, 74a, 74b 74c, 74d ... Magnets 75, 75a, 75b, 75c, 75d, 76, 76a, 76b, 76c, 76d ... Electrodes 77 ... First regulating means 78 ... Second regulating means

Claims (2)

A cylinder with a conductive fluid sealed inside;
A piston that partitions the cylinder into a first fluid chamber and a second fluid chamber;
A flow having an overall length longer than a length dimension along the moving direction of the piston and provided in the piston to allow the conductive fluid to flow between the first fluid chamber and the second fluid chamber. Road,
A magnet provided on a side surface of the flow path in the piston;
The piston is provided on a side surface of the flow path so as to face a direction intersecting with a direction in which the magnetic flux formed by the magnet extends, and when the piston moves with respect to the cylinder, the conductive fluid flows. A shock absorber comprising an electrode for taking out a current flowing when passing through a road. The piston includes a plurality of flow paths;
One flow path allows the conductive fluid to flow from the first fluid chamber to the second fluid chamber, and the conductive fluid flows from the second fluid chamber to the first fluid. With a first restricting means that prohibits flow to the chamber,
The other flow path allows the conductive fluid to flow from the second fluid chamber to the first fluid chamber, and the conductive fluid flows from the first fluid chamber to the second fluid. The shock absorber according to claim 1, further comprising a second restricting means for prohibiting flow to the chamber.

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