JP5625790B2 - Cylinder device - Google Patents

Description

  The present invention relates to a cylinder device provided between two objects that move relative to each other, and more particularly, to a cylinder device that functions as a colloidal damper by containing a porous body having pores and hydraulic fluid.

  The cylinder device described in the following patent document contains a colloidal solution in which a porous material such as hydrophobized porous silica gel and a working fluid are mixed, and operates on the pores of the porous material. It is configured to expand and contract as the liquid flows in and out. And it is comprised so that the energy applied from the outside may be dissipated and it may function as a damper, when hydraulic fluid repeatedly flows in and out to the pore under the action of surface tension. A cylinder device that contains a colloidal solution therein is called a colloidal damper and has the characteristics described above. The colloidal damper has characteristics not found in conventional hydraulic dampers, for example, the amount of energy dissipation depends on the amplitude, and is expected to be applied in various fields.

JP 2004-44732 A JP 2008-309250 A

  The cylinder device functioning as a colloidal damper described in the above-mentioned patent document is still under development, leaving much room for improvement. Therefore, it is considered that the practicality of the cylinder device functioning as the colloidal damper is improved by making various improvements. This invention is made | formed in view of such a situation, and makes it a subject to provide the cylinder apparatus which functions as a highly practical colloidal damper.

In order to solve the above problems, a cylinder device of the present invention includes a sealed container that seals a porous body and a first hydraulic fluid inside a chamber defined by a housing and a piston. A colloidal sealing body that allows a change in the internal volume due to deformation of the flexible portion of the sealed container is contained, the sealed container comprising (A) a container body, (B) a porous body, and A part of the first working fluid is inserted into the opening in a state where it is placed in the entire body part of the container body and a part of the opening, and the porous body and a part of the first working fluid are inserted into the container body And (C) a lid that seals the remaining portion of the first hydraulic fluid in a space that is formed between the plug and the plug and closes the opening. It is, in a state where the plug body is inserted into the opening of the container body It prohibits the passage of the porous body, and is characterized in that to permit the passage of air.

  When the specific gravity of the porous body is substantially the same or smaller than the specific gravity of the working fluid, the porous body may float on the working fluid. In such a case, there is a problem that when the porous body and the working fluid are sealed, the porous body is scattered by wind or the like, or air is mixed into the space. The cylinder device of the present invention prepares a container for sealing the porous body and the first working fluid, and prevents the porous body from being dispersed because the porous body is pressed by the plug when sealing in the container. In addition, it is possible to suppress air contamination by the plug body. By having such an advantage, the cylinder device of the present invention is highly practical.

Aspects of the Invention

  In the following, some aspects of the invention that can be claimed in the present application (hereinafter sometimes referred to as “claimable invention”) will be exemplified and described. As with the claims, each aspect is divided into sections, each section is numbered, and is described in a form that cites the numbers of other sections as necessary. This is merely for the purpose of facilitating the understanding of the claimable inventions, and is not intended to limit the combinations of the constituent elements constituting those inventions to those described in the following sections. In other words, the claimable invention should be construed in consideration of the description accompanying each section, the description of the embodiments, etc., and as long as the interpretation is followed, another aspect is added to the form of each section. In addition, an aspect in which some constituent elements are deleted from the aspect of each item can be an aspect of the claimable invention.

In each of the following items, a combination of the technical features of (1) and (2) corresponds to claim 1, and the technical feature of (2) is added to claim 1. The technical features of (3) are added to claim 2 according to claim 1 or claim 2 with addition of the technical features of (3) to claim 3, or (4) to any one of claims 1 to 3. The technical feature of claim is added to claim 4, and the technical feature of claims (7) and (8) is added to any one of claims 1 to 4 in claim 5. The technical features of (9) and (10) are added to any one of claims 1 to 5 and correspond to claim 6 respectively.

(1) a housing connected to one of two objects that move relative to each other;
A piston coupled to the other of the two objects and slidable within the housing;
(A) a porous body having a large number of pores and a first hydraulic fluid contained in a chamber defined by the housing and the piston, and (B) a flexible flexible portion. A colloidal seal that includes the porous body and a sealed container that seals the first hydraulic fluid therein, and allows a change in the internal volume by deforming the flexible portion of the sealed container. Body,
A second working fluid filled inside the chamber and outside the colloid seal,
In response to the relative movement of the two objects, the first hydraulic fluid flows into and out of the pores of the porous body, thereby attenuating the relative movement of the two objects, thereby providing a colloidal damper. A functioning cylinder device,
The sealed container comprises:
A container main body having a trunk portion in which the flexible portion is formed and a cylindrical opening, and being a main body for accommodating the porous body and the first hydraulic fluid therein;
The porous body and a part of the first hydraulic fluid are inserted into the opening in a state where the porous body and a part of the first hydraulic fluid are put in the whole body part and a part of the opening. A plug for sealing the inside of the container body;
A cylinder device configured to close the opening of the container main body, and to cover the remaining portion of the first hydraulic fluid in a space defined between itself and the stopper in the opening. .

  The cylinder device described in this section, in which the colloidal solution in which the porous body and the hydraulic fluid are mixed, is called a colloidal damper and has a surface tension with respect to the pores of the porous body. It is configured to dissipate energy applied from the outside by repeatedly flowing in and out of the working fluid under the action. Such a colloidal damper has a problem that, for example, air is mixed when the porous body and the hydraulic fluid are sealed. In particular, if the specific gravity of the porous body is small or about the same as that of the hydraulic fluid, the porous body may float in the hydraulic fluid and more air may be mixed. In such a case, the porous body floating in the working fluid may be scattered by wind or the like.

  The cylinder device described in this section is based on the premise that the colloidal solution is sealed in a sealed container, and in a state where the porous body and a part of the first working fluid are put in the sealed container, It is sealed by a plug. That is, in the cylinder device of this section, when sealing in the container, it is possible to press the porous body with the plug before closing the opening with the lid. As a result, it is possible to prevent the porous body from being dispersed and to reduce the amount of air mixed by discharging air through the plug, as compared with the case where the opening is closed only by the lid.

  The “plug body” described in this section may be anything that inhibits at least the passage of the porous body in order to press the porous body. Therefore, the plug may be one that prohibits the passage of the first hydraulic fluid or air, or may allow the passage thereof. Specifically, for example, a rubber member, a felt filter, or the like can be used as the plug. When the plug is inserted into the opening, it is desirable that the plug can be moved in the opening to expel air. On the other hand, it is desirable that after the colloidal solution is sealed, the colloidal solution remains in that position and does not move. Therefore, for example, as will be described in detail later, the plug body can be elastically deformed, inserted into the opening while being elastically deformed, and cannot be moved by its own elastic force. Moreover, since the “lid” described in this section is for closing the opening and sealing the container body, it is possible to prohibit the passage of everything.

  The “sealed container” described in this section allows a change in the volume of the colloidal solution due to the inflow / outflow of the first working fluid into the porous body while maintaining the sealed state of the colloidal solution. That is, the cylinder device described in this section is configured such that the inner volume of the colloid sealed body changes according to the relative movement of the two objects that move relative to each other, in other words, the volume of the colloid sealed body changes. ing. Note that the sealed container may generate a force that restores its deformation, or may not generate the force that restores. As the sealed container, for example, various ones such as a bag-like one, a stretchable one, and an elastic one can be adopted. In addition, the material of the sealed container is not particularly limited, and a sealed container formed of rubber or metal can be used.

  The cylinder device described in this section uses a colloidal solution in which “porous body” and “first hydraulic fluid” are mixed. The types of the “porous body” and the “first hydraulic fluid” are not particularly limited, but they are low in affinity with each other and are difficult to bind to each other. It is desirable that it is difficult to dissolve in the liquid. As the “porous body”, it is possible to adopt μm (micrometer) order granular material (microparticle) having pores of nm (nanometer) order, for example, the first operation with lyophobic property. It is possible to adopt one that does not dissolve easily in the liquid or one that is coated with a lyophobic substance. Specifically, for example, silica gel, aerogel, ceramics, zeolite, porous glass, porous polystyrene, or the like can be adopted as the porous body. In addition, for example, water, a mixed solution of water and an antifreezing agent (ethanol, ethylene glycol, propylene glycol, glycerin, etc.), mercury, molten metal, or the like can be used as the “first working fluid”. Since water has a relatively large surface tension, when water is used as the first working fluid, a large force is applied due to the large surface tension when water flows into and out of the pores of the porous body. It becomes a colloidal damper to be generated. In addition, when water is used for the first hydraulic fluid, as described above, it is desirable to use a porous body having a low hydrophilicity or a hydrophobized one.

  The “second hydraulic fluid” described in this section exists inside the chamber and outside the colloid seal. In other words, the cylinder device of this section is configured to transmit the force applied to the housing and the piston to the colloid sealing body via the second hydraulic fluid. The “second working fluid (outside the container working fluid)” and the above “first working fluid (the inside working fluid in the container)” may be the same liquid or may be different from each other in nature. Good. From the viewpoint of easy transmission of the force applied to the housing and the piston to the colloidal sealed body, it is desirable to employ a high viscosity fluid as the second hydraulic fluid.

(2) The plug is
The cylinder device according to (1), wherein in the state inserted into the opening of the container body, the passage of the porous body and the first hydraulic fluid is prohibited and the passage of air is allowed. .

  The aspect described in this section is limited to a filter through which the plug passes air. If the plug described in this section is used, air can be expelled from the space that seals the porous body and part of the first hydraulic fluid when the plug is inserted into the opening. The described cylinder device is a cylinder device with a small amount of air.

(3) The plug is
Item (1) or Item (2), which is elastically deformable and remains inside the opening by elastic force to seal part of the porous body and the first hydraulic fluid. Cylinder device.

  When the “plug body” described in this section is used, when assembling the colloid sealing body, the plug body can be pushed in while being elastically deformed and inserted into the opening. That is, since the plug can be inserted while air is expelled from the gap between the opening and the plug, the cylinder device described in this section is a cylinder device with a small amount of air.

(4) The opening of the container body is formed in a cylindrical shape having a constant cross-sectional shape,
The cylinder device according to any one of (1) to (3), wherein the plug has the same cross-sectional shape as the cross-sectional shape of the opening.

  In the aspect described in this section, the shape of the opening is limited. In the aspect of this section, since the cross-sectional shape of the opening of the container main body is constant, it can be smoothly inserted when the plug is inserted into the opening.

  (5) The cylinder device according to any one of (1) to (4), wherein the body portion of the container body is formed in a cylindrical shape.

  In the embodiment described in this section, the shape of the sealed container is limited. In other words, according to the aspect of this section, the colloid sealing body is generally cylindrical. Therefore, the cylinder device and the colloid sealed body according to the aspect of this section are well-contained in the housing, and have a clean structure.

  (6) The cylinder device according to item (5), wherein the flexible part formed on the body part has a bellows shape.

  In the embodiment described in this section, the shape of the sealed container is limited, and the bellows-like flexible part is expanded and contracted. In other words, the aspect of this section is configured such that the volume of the colloid sealing body changes as the colloid sealing body expands and contracts. In the aspect of this section, for example, the colloid sealing body is accommodated in the housing so that the direction in which the flexible portion expands and contracts is the same as the direction in which the piston slides. The inner wall can be prevented from contacting.

(7) The housing is
The cylinder device according to any one of (1) to (6), including a cylindrical body in which the piston slides and a closing body that closes an end of the cylindrical body.

  In the aspect described in this section, the configuration of the housing is embodied. The “occlusion body” described in this section is for sealing the opening of the cylindrical body in order to prevent leakage of the second hydraulic fluid contained in the housing. May be.

  (8) The cylinder device according to (7), wherein the closing body of the housing and the lid body of the sealed container are integrally formed.

  The aspect described in this section can be, for example, an aspect in which the closing body and the lid are a single member or an aspect in which the cylinder device is assembled. For example, by assembling a closed body and lid integrated into the container body, completing the colloidal sealed body, and assembling the unit containing the colloidal sealed body into the cylinder body, it is easy to assemble A possible cylinder device is realized. From the viewpoint of simplifying the assembly of the cylinder device, it is desirable that the closing body and the lid are a single member.

  In the cylinder device described in this section, the colloid sealing body is fixed to the end of the housing. In the aspect of this section, it is possible to prevent the colloid sealing body from coming into contact with the piston, thereby preventing the piston from sliding in the housing.

  (9) The cylinder device according to any one of (1) to (8), wherein the first hydraulic fluid is water.

  (10) The cylinder device according to (9), wherein the porous body is a hydrophobized porous body.

  The embodiments described in the above two items are limited in the configuration of the colloidal solution. As described above, since water has a large surface tension, it is suitable as a working fluid for a colloidal damper. When the working fluid is water, the porous body is desirably hydrophobic, and the latter mode is a desirable mode. In the aspect of this section, since the porous body has hydrophobicity, depending on the specific gravity of the porous body, the porous body tends to float on the water that is the first working fluid. Therefore, in the embodiment of this section, a sealed container having a configuration in which the hydrophobic porous body and water are sealed in the container body by the stopper is particularly effective.

  (11) The cylinder device according to any one of (1) to (10), wherein the second hydraulic fluid is oil.

  In the aspect described in this section, the second hydraulic fluid is limited, and as the second hydraulic fluid, for example, mineral oil or silicone oil that is a synthetic oil can be employed. Consider a cylinder device having a configuration in which the aspect of this section and the aspect of using the first hydraulic fluid described above as water are combined. In general, since the viscosity of oil is higher than that of water, it is possible to efficiently transmit the force applied to the housing and the piston to the colloidal seal. Further, for example, when the present cylinder device is configured to support an object located on the upper side, the pressure in the chamber becomes relatively high. That is, in such a cylinder device, it is necessary to ensure the sealing performance of the seal provided in the housing in order to keep the inside of the chamber at a high pressure. Oil with high viscosity is difficult to leak from the seal, and is particularly effective in a cylinder apparatus that needs to keep the inside of the chamber at a high pressure as described above. In general, oil has good lubricity, and the sliding of the piston in the housing can be made smooth.

  In general, the solidification temperature of oil is lower than the solidification temperature of water. For example, when the second hydraulic fluid starts to solidify, there is a possibility that the force transmitted to the colloid sealing body may fluctuate with respect to the force applied to the housing and the piston. However, according to the aspect of this section, it is possible to reliably transmit the force applied to the housing and the piston to the colloid sealing body by the oil that is hard to solidify.

  Furthermore, in general, the thermal conductivity of oil is lower than the thermal conductivity of water. Although the water in the colloidal solution may solidify due to a decrease in the outside air temperature, the temperature of the water in the colloidal solution can be set outside by the oil with low thermal conductivity by configuring the colloidal sealing body to be covered with oil. It is possible to suppress escape and prevent water from solidifying.

(21) A cylinder device assembling method for assembling the cylinder device according to any one of (1) to (11),
A sealing body assembling step for assembling the colloidal sealing body,
The sealing body assembly process
A colloid injection step of putting the porous body and the first working fluid into the body portion and a part of the opening of the container body;
A colloid sealing step of inserting the plug into the opening and sealing the porous body and a part of the first hydraulic fluid in a sealed space defined by the plug and the container body;
The container body in which the porous body and a part of the first hydraulic fluid are sealed inside by the colloid sealing step is placed in a hydraulic fluid tank filled with the same hydraulic fluid as the first hydraulic fluid. And a lid assembly process for closing the opening with the lid in the hydraulic fluid tank.

  In the aspect described in this section, the category is the assembling method of the cylinder device. More specifically, the cylinder device assembling method described in this section is characterized by the assembling method of the colloid sealing body. According to the assembling method of this section, it is possible to prevent the porous body from being dispersed and to suppress the amount of air mixed into the colloid sealed body as compared with the case where the opening is closed only by the lid.

(22) The housing is
A cylindrical body in which the piston slides, a closed body that closes the end of the cylindrical body, and a liquid-tight space between the cylindrical body and the closed body interposed between the cylindrical body and the closed body And a seal for sealing,
The cylinder device assembling method is
Inserting the colloid sealing body assembled by the piston and the sealing body assembly step into the cylindrical body of the housing and filling the cylindrical body with the second hydraulic fluid, the end of the cylindrical body is A cylinder assembly step of assembling the cylinder device by closing with a closing body;
In the cylinder assembling step, when the end of the cylindrical body is closed with the closing body, the seal comes into contact with both the cylindrical body and the closing body, and then one of the cylindrical body and the closing body is changed to the other. Considering the displacement of the piston caused by the volume change of the chamber caused by tightening, the piston after closing the end of the cylindrical body with the closing body becomes the set position. The cylinder device assembling method according to the item (21), wherein the tightening is performed by arranging the inside of the cylinder.

  Let us consider a case where the opening of the cylinder is closed by a closing body in the process of assembling the housing. In order to ensure the fluid tightness of the housing in which the second hydraulic fluid is accommodated, a seal is interposed between the cylindrical body and the closing body. When the closure body is assembled to the cylinder body, when the position of the closure body relative to the cylinder body reaches a position where the seal functions, the liquid tightness of the housing is ensured at that time. In order to firmly assemble the closure body with respect to the cylinder body, it is necessary to further tighten the closure body and the cylinder body. However, in order to tighten further from the time when the liquid tightness of the housing is ensured, it is necessary to increase the pressure in the chamber or increase the volume change in the chamber that decreases by the tightening by another mechanism or the like. .

  In the cylinder device assembling method described in this section, the reduction in the volume of the chamber due to the tightening of the cylinder and the closing body is canceled by the movement of the piston inserted into the cylinder. Specifically, the piston protrudes to the outside of the cylinder by the movement of the piston, and the increase in the chamber volume due to the protrusion cancels the decrease in the chamber volume due to the tightening of the cylinder and the closing body. In the cylinder device assembling method of this section, the piston is inserted into the cylinder in consideration of the displacement of the piston due to the tightening of the cylinder and the closing body. Put simply, a large number of pistons are inserted into the cylinder. Therefore, even if the piston moves when the closed body is assembled to the cylindrical body, the position of the piston with respect to the housing at the completion of the assembly of the cylinder device is the set position.

It is a front view of the suspension device for vehicles which used the cylinder device which is an example of claimable invention as one component. It is front sectional drawing of the cylinder apparatus which is an Example of claimable invention. It is sectional drawing which shows the porous body shown in FIG. 2 typically. It is front sectional drawing of the colloidal damper of the simple structure conventionally known. It is a figure which shows the relationship between the stroke in the colloidal damper shown in FIG. 4, and the pressure in a chamber. It is a figure which shows the relationship between the stroke in the cylinder apparatus which is an Example of claimable invention, and the pressure in a sealed container. It is a figure which shows the state which divided | segmented the cylinder apparatus which is an Example of claimable invention into three parts. It is a figure which shows the assembly method of the bellows Assy (colloid sealing body) shown in FIG. It is a figure which shows the method of assembling three parts shown in FIG.

  Hereinafter, representative embodiments of the claimable invention will be described in detail with reference to the drawings. In addition to the following examples, the claimable invention is implemented in various modes including various modifications and improvements based on the knowledge of those skilled in the art, including the mode described in the above [Mode of Invention]. can do.

<Configuration of suspension device>
As shown in FIG. 1, the cylinder device 10 of the present embodiment is a component of a vehicle suspension device. The vehicle suspension device is an independent suspension type provided corresponding to each of the wheels 12 of the vehicle, and is a multi-link suspension device. The suspension device includes a first upper arm 20, a second upper arm 22, a first lower arm 24, a second lower arm 26, and a toe control arm 28, each of which is a suspension arm. One end of each of the five arms 20, 22, 24, 26, 28 is rotatably connected to the vehicle body, and the other end is an axle carrier 30 as a wheel holding member that rotatably holds the wheel 12. It is connected to the pivotable. By these five arms 20, 22, 24, 26, and 28, the axle carrier 30 is allowed to move up and down along a certain locus with respect to the vehicle body. The cylinder device 10 is disposed between a mount portion 32 provided on a tire housing that is a part of the vehicle body and the second lower arm 26.

  FIG. 2 is a front sectional view of the cylinder device 10. The cylinder device 10 includes a generally cylindrical housing 40 and a piston 42 slidably disposed with respect to the housing 40. The housing 40 is configured to include a tube 44 that slides the piston 42, an upper lid 46 that closes the upper end portion of the tube 44, and a bottom lid 48 that closes the lower end portion of the tube 44. The piston 42 has a piston main body 50, and the piston main body 50 divides the inside of the housing 40 into an upper chamber 52 and a lower chamber 54, which are two chambers, sandwiching itself. The piston 42 further includes a piston rod 58, which is connected to the piston main body 50 at the lower end portion and extends from the upper lid 46 of the housing 40. The piston rod 58 is connected to the lower surface side of the mount portion 32 via an upper support 62 configured to include an anti-vibration rubber 60 at the upper end portion. On the other hand, the housing 40 is connected to the second lower arm 26 via a bushing 64 at the lower end thereof.

  That is, the housing 40, the piston rod 58, and the piston 42 coupled thereto can be relatively moved in the axial direction in accordance with the approach and separation between the vehicle body (mount portion 32) and the wheel 12 (axle carrier 30). Yes. In other words, the cylinder device 10 can be expanded and contracted in accordance with the approach and separation between the vehicle body and the wheel 12.

  Incidentally, the cylinder device 10 includes a cover tube 66. The cover tube 66 accommodates the piston rod 58 and the upper portion of the housing 40, and prevents entry of dust, mud, and the like from the outside. Yes.

  Inside the housing 40, a colloid sealing body 72 in which the colloid solution 70 is sealed is provided. The colloidal solution 70 is a mixture of hydrophobized porous silica gel 74 and water 76 as a first working fluid. The colloid sealing body 72 includes the hydrophobic porous silica gel 74 and water 76 and a sealed container 78 that seals them.

  The sealed container 78 has a bellows case 80 as a container main body which is a main body for accommodating the hydrophobic porous silica gel 74 and the water 76. The bellows case 80 is made of metal and has a generally cylindrical body portion 82 and an opening 84 having an outer diameter smaller than the outer diameter of the body portion 82. The body portion 82 is formed in a bellows shape, and the bellows case 80 is expanded and contracted when the body portion 82 expands and contracts. Further, the bellows case 80 has a male screw formed on the outer peripheral surface of the opening 84, and the male screw is engaged with a female screw formed on the bottom lid 48 of the housing 40, thereby closing the opening 84. ing. Further, a packing 86 is fitted into the opening 84 of the bellows case 80, and the hydrophobic porous silica gel 74 and water 76 are sealed in the bellows case 80 by the packing 86. Incidentally, the packing 86 is a felt-like filter, which prohibits the passage of the hydrophobic porous silica gel 74 and the water 76 and allows the passage of air. The characteristics of the cylinder device 10 by providing the packing 86 will be described in detail later. From the above configuration, the sealed container 78 includes a bellows case 80 as a container body, a packing 86 as a plug for sealing the hydrophobic porous silica gel 74 and water 76 inside the bellows case 80, and a bellows case. And a bottom lid 48 as a lid that closes the opening 84 of the 80. The bottom lid 48 not only functions as a closing body that closes the end of the tube 44 but also functions as a lid that closes the opening 84 of the container body, and the configuration of the cylinder device 10 is simple. It has become.

  FIG. 3 schematically shows a cross-sectional view of one particle of the hydrophobized porous silica gel 82. Hydrophobized porous silica gel particles 100 are spherical silica gel particles having an outer diameter D on the order of several μm to several tens of μm and an inner diameter d of the pores 102 on the order of several nm to several tens of nm. (Including the inside) is hydrophobized with a hydrophobic substance. That is, each of the hydrophobized porous silica gel particles 100 functions as a porous body.

  The lower chamber 54 is filled with a mineral oil 110 as a second working fluid in a state in which the colloid sealing body 72 is accommodated. The upper chamber 52 is also filled with mineral oil 110. The piston body 50 described above is provided with a plurality of communication passages 112 that penetrate the piston main body 50 in the axial direction and communicate the upper chamber 52 and the lower chamber 54. That is, when the volumes of the upper chamber 52 and the lower chamber 54 change as the piston 42 slides with respect to the housing 40, the mineral oil 110 is transferred between the upper chamber 52 and the lower chamber 54 by the communication passage 112. Distribution is allowed. Incidentally, as will be described in detail later, since the inside of the housing 40 has a high pressure, a plurality of lids at the upper end portion and the lower end portion of the housing 40 are provided in order to prevent the mineral oil 110 from leaking. High pressure seals 114 and 116 are provided. In particular, two seals 116 that are in contact with the sliding surface of the piston rod 58 are provided on the lid at the upper end where the piston rod 58 slides. Grease is sealed between the two seals 116 to improve the sealing performance.

  The cylinder device 10 includes a mechanism that restricts the approaching and separating operation between the vehicle body and the wheels, a so-called bound stopper, and a rebound stopper. Specifically, the bound stopper is configured to include an annular buffer rubber 140 attached to the upper end inside the cover tube 66, and the upper end portion of the housing 40 contacts the cover tube 66 via the buffer rubber 140. It is configured to touch. The rebound stopper includes an annular cushioning rubber 142 attached to the lower surface of the upper lid portion of the housing 40, and the upper surface of the piston 42 and the upper lid portion of the housing 40 constitute the cushion rubber. It is comprised so that it may contact | abut via 142.

<Characteristics as colloidal damper>
i) Characteristics of General Colloidal Damper As described above, the present suspension device is mainly composed of the cylinder device 10, and the cylinder device 10 is a colloidal damper that accommodates the colloidal solution 70 therein. The function of the cylinder device 10 as a colloidal damper will be described in detail below. First, before describing the cylinder device 10, general characteristics of the colloidal damper will be described in detail with reference to FIG. 5 taking the colloidal damper 150 having a simple configuration shown in FIG. 4 as an example. The colloidal damper 150 includes a cylinder device 156 that includes a housing 152 and a piston 154 that slides in the housing 152. In the colloidal damper 150, a chamber 158 formed by the housing 152 and the piston 154 is filled with a colloidal solution 164 in which a porous body 160 and a working fluid 162 are mixed.

  FIG. 5 is a diagram showing the relationship between the relative movement amount S (stroke of the cylinder device 156) between the housing 152 and the piston 154 and the internal pressure p of the chamber 158. In the colloidal damper 150, when a force for contracting the cylinder device 156 is applied from the outside, first, the hydraulic pressure of the hydraulic fluid 162 in the chamber 158 increases greatly (with a steep gradient) (range (I) in FIG. 5). . When the hydraulic pressure of the hydraulic fluid 162 rises to a certain height, the hydraulic fluid 162 starts to flow into the pores of the porous body 160 against the surface tension of the hydraulic fluid 162, and the magnitude of the applied force is increased. The hydraulic fluid 162 flows in by a proportional amount (range (II) in FIG. 5). Due to the flow of the working fluid 162 into the porous body 160, the volume of the colloidal solution 164 decreases, and the cylinder device 156 is stroked to contract. That is, the inflow amount of the hydraulic fluid 162 and the volume change of the chamber 158 are equal, and it can be said that the inflow amount of the hydraulic fluid 162 and the stroke of the cylinder device 156 are in a linear relationship. Further, as the amount of the hydraulic fluid 162 flowing in increases, the internal pressure of the chamber 158 also increases. That is, as shown in the range of (II) in FIG. 5, the stroke S of the cylinder device 156 and the internal pressure p of the chamber 158 have a linear relationship. Then, when the hydraulic fluid 162 flows into the porous body 160 to the vicinity where it can flow, the hydraulic pressure of the hydraulic fluid 162 starts to increase greatly (range (III) in FIG. 5).

  Next, when the force applied to the cylinder device 156 is removed, the hydraulic pressure of the hydraulic fluid 162 is greatly reduced (with a steep slope) (range (IV) in FIG. 5). Thereafter, when the hydraulic pressure of the hydraulic fluid 162 decreases, the hydraulic fluid 162 flows out from the pores of the porous body 160 (range (V) in FIG. 5). Due to the outflow of the working fluid 162 from the porous body 160, the volume of the colloidal solution 164 increases, and the cylinder device 156 performs a stroke operation so as to extend. In the case where the hydraulic fluid 162 shown in the range of (V) in FIG. 5 flows out, the stroke S of the cylinder device 156 and the internal pressure p of the chamber 158 are linear as in the case where the hydraulic fluid 162 flows in. It has become a relationship.

  If the state between the porous body 160 and the working fluid 162 is described using the contact angle between the porous body 160 and the working fluid 162, the working fluid 162 flows into the porous body 160. The contact angle is large, and the contact angle decreases when the hydraulic fluid 162 flows out of the porous body 160. Therefore, as shown in FIG. 5, there is a difference between the internal pressure of the chamber 158 when the hydraulic fluid flows in (shrinks) and the internal pressure of the chamber 158 when the hydraulic fluid flows out (extension). That is, as shown in FIG. 5, hysteresis occurs in the change in the internal pressure p of the chamber 158 with respect to the change in the stroke S of the cylinder device 156. As a result, the colloidal damper 150 is configured to dissipate energy and attenuate the relative movement of two relatively moving objects. Incidentally, the area surrounded by the hysteresis in FIG. 5 corresponds to the dissipated energy.

ii) Characteristics of the Cylinder Device as a Colloidal Damper In this cylinder device 10, the colloidal solution 70 is sealed in the sealed container 78, but the force applied from the outside is applied to the sealed colloid 72 through the mineral oil 110. Is transmitted to. Then, when a force is applied to the colloid sealing body 72, the hydraulic pressure of the water 76 accommodated in the sealed container 78 increases. When the hydraulic pressure of the water 76 rises to a certain height, the water 76 flows into the pores 102 of the hydrophobic porous silica gel particles 100 against the surface tension. As a result, the sealed container 78 contracts, and the volume of the colloid sealed body 72 decreases. On the other hand, when the force applied to itself is lost, the hydraulic pressure of the water 76 decreases, and the water 76 flows out from the pores 102 of the hydrophobic porous silica gel particles 100. Along with this, the sealed container 78 expands, and the volume of the colloid sealed body 72 increases. That is, the cylinder device 10 also has the same characteristics as the colloidal damper 150 described above. FIG. 6 shows the relationship between the stroke S of the cylinder device 10 and the internal pressure p of the colloid sealing body 72.

<Function of this cylinder device>
i) Function as Suspension Spring As described above, the cylinder device 10 is a main component of the suspension device. First, the cylinder device 10 has a function as a suspension spring. The cylinder device 10 is disposed between the mount portion 32 and the second lower arm 26, and receives a shared load (so-called 1W) of the wheel 12 corresponding to the cylinder device 10 and contracts. When the cylinder device 10 contracts, a certain amount of water 76 flows into the pores 102 of the hydrophobized porous silica gel particles 100, and the pressure in the colloid sealing body 72 increases. The cylinder device 10 is responsible for the wheel's shared load by the force generated depending on the internal pressure of the colloid sealing body 72.

  As shown in FIG. 6, the cylinder device 10 is configured so that all water 76 does not flow out from the pores 102 of the hydrophobized porous silica gel particles 100 within a range where the stroke is allowed. The amount of water 76 flowing into the pores 102 of the hydrophobized porous silica gel particle 100 does not reach a limit value at which it can flow. As can be seen from FIG. 6, when the stroke is made so that the volume of the lower chamber 54 in which the colloid sealing body 72 is accommodated is reduced, in other words, when the cylinder device 10 is stroked to contract, the colloid sealing is performed. The internal pressure p of the body 72 is proportional to the amount of water 76 flowing into the pores 102 of the hydrophobic porous silica gel particles 100. The amount of water 76 flowing into the pores 102 of the hydrophobized porous silica gel particles 100 is equal to the volume of the piston rod 58 that has entered the housing 40. That is, the internal pressure p of the colloid sealing body 72 has a magnitude proportional to the stroke amount of the cylinder device 10 (the relative operation amount between the vehicle body and the wheel holding member). Therefore, it can be considered that the cylinder device 10 generates a force responsible for 1 W in the entire stroke range of the cylinder device 10 determined by the rebound stopper and the bound stopper.

By the way, the cylinder device 10 is configured so that the internal pressure p of the colloid sealing body 72 strokes within a range proportional to the amount of water 76 flowing into the pores 102 of the hydrophobic porous silica gel particles 100. The amount (volume) of the hydrophobized porous silica gel 74 accommodated in the colloid sealing body 72 and the amount (volume) of water 76 are determined. First, in the cylinder device 10, from the neutral position in the standard state (for example, the state where no one is on the vehicle, nothing is loaded, and the vehicle is stopped on the horizontal plane), the bound direction If the stroke amount S _b can be stroked in the rebound direction by the stroke amount S _r, the volume change ΔV that combines the upper chamber 52 and the lower chamber 54 of the cylinder device 10 will be different between full bound and full rebound. It is obtained as follows.
ΔV = A · (S _b + S _r )
Here, A is a pressure receiving area which is an area where the pressure in the housing 40 acts on the piston 42, and in the cylinder device 10, the cross sectional area of the piston rod 58 corresponds to it.

In the cylinder device 10, it is necessary that an amount of water 76 equal to the volume change ΔV can flow into the hydrophobic porous silica gel 74. That is, if the ratio of the limit value at which the water 76 of the hydrophobic porous silica gel 74 can flow into the volume of the hydrophobic porous silica gel 74 is η, the necessary minimum amount (volume) of the hydrophobic porous silica gel 74 V _Smin Is determined by the following equation.
V _Smin = ΔV / η
In the hydrophobic porous silica gel 74, there is a case where all of the hydrophobic silica gel 74 is not hydrophobized and the water-absorbing silica gel remains. For example, if the ratio of the amount of hydrophobized silica gel excluding the amount of non-hydrophobized silica gel to the total amount subjected to hydrophobization treatment is defined as the hydrophobization rate β, the variation in the hydrophobization rate, etc. To accommodate this, the actual amount (in volume) V _S of the hydrophobized porous silica gel 86 is determined by the following equation and is greater than its required minimum amount V _{Smin of} the hydrophobized porous silica gel 86.
V _S = V _Smin / β
In addition, since the amount V _{F of the} water 76 should be ΔV or more with respect to the amount V _{S of} the hydrophobic porous silica gel 74, in the cylinder device 10, V _F = V _S.

ii) Function as Shock Absorber In this cylinder device 10, if the change in the internal pressure of the colloid sealing body 72 in one cycle of operation from the neutral position is shown in relation to the stroke S of the cylinder device 10, the two shown in FIG. It looks like a dotted line. Similarly to the general colloidal damper 150 described above, the cylinder device 10 includes the internal pressure of the colloid sealing body 72 when the hydraulic fluid flows in (shrinks) and the colloidal sealing body 72 when the hydraulic fluid flows out (extension). As shown in FIG. 6, there is a difference in the internal pressure p of the colloid sealing body 72 with respect to the change of the stroke S of the cylinder device 10, as shown in FIG. 6. The area surrounded by the two-dot chain line in FIG. 6 corresponds to the energy dissipated in one cycle of operation. That is, the cylinder device 10 attenuates the relative movement between the vehicle body and the wheel 12, and functions as a shock absorber.

<Assembly method of this cylinder device>
As described above, the cylinder device 10 is configured such that the sealed container 78 that seals the hydrophobic porous silica gel 74 and the water 76 includes the packing 86 as a plug inside. Since the packing 86 is effective when the cylinder device 10 is assembled, the assembly method of the cylinder device 10 will be described in detail below. As shown in FIG. 7, the cylinder device 10 is roughly divided into three parts. These three parts include a tube 44 constituting the housing 40, a piston Assy 180 constituted by including the piston 42 and an upper lid 46 constituting the housing 40, a colloid sealing body 72 and a bottom lid 48 constituting the housing. It is the bellows Assy182 comprised. First, the assembly method of the bellows Assy 182, that is, the assembly method of the colloid sealing body 72 will be described in detail with reference to FIG. 8.

i) Colloid Seal Assembly Step The first step for assembling the bellows Assy 182 is a colloid injection step for putting the colloid solution 70 into the bellows case 80. That is, the bellows case 80, the amount of the hydrophobized porous silica gel 74 described above, and the water 76 are prepared. Then, as shown in FIG. 8A, the hydrophobized porous silica gel 74 and water 76 are placed in the bellows case 80. In the state where the hydrophobic porous silica gel 74 and the water 76 are placed in the bellows case 80, the middle of the opening 84 of the bellows case 80 is filled with the hydrophobic porous silica gel 74 and the water 76. The amount of water 76 is adjusted. Incidentally, the surface of the hydrophobized porous silica gel 74 is hydrophobized and its specific gravity is relatively small, so that it is floated on the water 76.

  The next step is a colloid sealing step for sealing the hydrophobic porous silica gel 74 and water 76 placed in the bellows case 80. Specifically, as shown in FIG. 8B, the packing 86 is inserted into the bellows case 80. As described above, the packing 86 is a filter that prohibits passage of the hydrophobic porous silica gel 74 and water 76 and allows passage of air. Further, the packing 86 is a disc-shaped one having an outer diameter slightly larger than the inner diameter of the opening 84 and is elastically deformable. That is, the packing 86 has elasticity, and is retained inside the opening 84 by the elastic force. When such a packing 86 is gradually inserted into the opening 84, air is expelled from the space formed by the bellows case 80 and the packing 86. Therefore, in the state where the hydrophobic porous silica gel 74 and the water 76 are sealed in the bellows case 80 by the insertion of the packing 86, air is prevented from being mixed.

  Next, as shown in FIG.8 (c), the water tank 190 which filled the inside with water is prepared. Then, a bellows case 80 in which the hydrophobic porous silica gel 74 and water 76 are sealed by the packing 86 is put in the water tank 190, and a space between the packing 86 and the opening end in the opening 84 of the bellows case 80 is provided. Filled with water. Next, as shown in FIG. 8D, the bottom lid 48 as a lid is assembled to the bellows case 80 in the water tank 190. The bottom lid 48 is a cylindrical object, and an internal thread is formed on the inner peripheral surface thereof. Then, the female screw is screwed into a male screw formed on the outer peripheral surface of the opening 84 to close the opening 84. A seal 192 is provided at the tip of the bottom lid 48, and the liquid seal inside the sealed container 78 is secured by the seal 192 coming into contact with the stepped portion of the bellows case 80. Incidentally, the tightening of the screw after the seal 192 abuts on the bellows case 80 is allowed by the expansion of the body portion 82 of the bellows case 80, so that the internal pressure of the sealed container 78 becomes high and the screw is tightened. There will be no situation where you cannot. That is, air is not mixed in the bellows case 80 also in this lid assembly process. Therefore, the colloid sealing body 72 is not mixed with air.

  Here, for example, a case where the container body is closed with a lid without using the packing 86 is considered. In this case, the hydrophobic porous silica gel 74 and water 76 are filled up to the end of the opening of the container body, and the opening is closed by the lid. As described above, since the hydrophobized porous silica gel 74 floats on the water 76, air is mixed even if the opening is closed by the lid in that state. Further, when the container main body is filled with the hydrophobized porous silica gel 74 and the water 76, the porous silica gel 74 is present at the end of the opening and may be scattered by wind or the like. That is, the amount of the hydrophobic porous silica gel 74 accommodated in the sealed container 78 is reduced. On the other hand, since the colloid sealing body 72 assembled as described above presses the hydrophobic porous silica gel 74 with the packing 86 before closing the opening 84 with the bottom lid 48, air is mixed as described above. In addition, the amount of the hydrophobized porous silica gel 74 is not reduced.

ii) Cylinder assembly step Next, a method for assembling the bellows Assy 182 and the piston Assy 180 assembled as described above to the tube 44 will be described in detail with reference to FIG. First, the piston assembly 180 is assembled to the tube 44. The piston assembly 180 has a piston rod 58 penetrating into the upper lid 46. When the piston assembly 180 is assembled to the tube 44, the piston main body 50 is inserted into the tube 44 as shown in FIG. The upper end of 44 is closed. Specifically, a female screw is formed on the inner peripheral surface of the upper end portion of the tube 44 and a male screw is formed on the outer peripheral surface of the upper lid 46. By screwing them together, the upper end of the tube 44 is connected to the piston assembly 180. Blocked by. (Piston insertion process)

  Next, a mineral oil tank 200 whose interior is filled with mineral oil as the second working fluid is prepared. Then, as shown in FIG. 9 (b), an assembly in which the tube 44 and the piston Assy 180 are assembled is placed in the mineral oil tank 200, and the inside of the tube 44 is filled with mineral oil. (Cylinder filling process)

  Next, the bellows Assy 182 is assembled to the tube 44 in the mineral oil tank 200. When assembled to the tube 44, as shown in FIG. 9C, the sealed container 78 is inserted into the tube 44, and the lower end of the tube 44 is closed by the bottom lid 48 serving as a closing body. Specifically, a female screw is formed on the inner peripheral surface of the lower end portion of the tube 44, and a male screw is formed on the outer peripheral surface of the bottom cover 48. By screwing them together, the lower end of the tube 44 is bellows. Blocked by Assy182. (Occlusion body assembly process)

Further, a seal 114 is provided at the lower end of the bottom lid 48. The seal 114 abuts against the inner peripheral surface of the tube 44, thereby ensuring liquid tightness inside the tube 44 (FIG. 9 (c). ) Incidentally, the tightening of the screw after the seal 114 comes into contact with the tube 44 is allowed by the movement of the piston main body 50 toward the upper lid 46, that is, the piston rod 58 protrudes to the outside. There is no situation where the internal pressure becomes high and the screws cannot be tightened. The cylinder device 10 is designed so that the relative position between the housing 40 and the piston 42 is fully rebound as shown in FIG. 9 (d) before the assembly is completed and assembled to the vehicle. ing. Therefore, if the outside length of the piston rod 58 at the fully rebound position is the standard protrusion length L _S , the rod protrusion that is the length of the piston rod 58 at the time when the seal 114 abuts the inner peripheral surface of the tube 44. The length L is shorter than the standard protrusion length L _S. More specifically, the amount of movement of the piston 42 is estimated based on the volume in which the bellows Assy 182 enters the tube 44 from when the seal 114 abuts the tube 44 until the screw tightening is completed. The rod protrusion length L is determined. For example, if the bellows Assy 182 is to be assembled at the fully rebound position, the internal pressure of the housing 40 becomes high after the seal 114 comes into contact with the tube 44, and the screw cannot be tightened. According to that, it will never happen.

  Incidentally, although the assembly method according to the above-described cylinder assembly process is to assemble the bellows Assy 182 after assembling the piston Assy 180, the piston Assy 180 may be assembled after the bellows Assy 182 is assembled. In this case, the rod protrusion length when the seal 114 provided on the upper lid 46 contacts the inner peripheral surface of the tube 44 may be the rod protrusion length L described above.

  10: Cylinder device (colloidal damper) 12: Wheel 26: Second lower arm 30: Axle carrier (wheel holding member) 32: Mount part (part of the vehicle body) 40: Housing 42: Piston 44: Tube (tubular body) 46: Upper lid 48: Bottom lid (lid body, closed body) 50: Piston body 52: Upper chamber 54: Lower chamber (chamber) 58: Piston rod 70: Colloid solution 72: Colloid sealing body 74: Hydrophobized porous silica gel 76: Water (First working fluid) 78: Sealed container 80: Bellows case (container main body) 82: Body part 84: Opening part 86: Packing (plug) 100: Hydrophobized porous silica gel particle (porous body) 102: Pore 110: Mineral oil (second hydraulic fluid) 112: Communication path 114, 116: High pressure Lumpur 180: Piston Assy 182: Bellows Assy 190: water tank 192: Seal 200: Mineral oil vessel

Claims (6)

A housing connected to one of the two relatively moving objects;
A piston coupled to the other of the two objects and slidable within the housing;
(A) a porous body having a large number of pores and a first hydraulic fluid contained in a chamber defined by the housing and the piston, and (B) a flexible flexible portion. A colloidal seal that includes the porous body and a sealed container that seals the first hydraulic fluid therein, and allows a change in the internal volume by deforming the flexible portion of the sealed container. Body,
A second working fluid filled inside the chamber and outside the colloid seal,
In response to the relative movement of the two objects, the first hydraulic fluid flows into and out of the pores of the porous body, thereby attenuating the relative movement of the two objects, thereby providing a colloidal damper. A functioning cylinder device,
The sealed container comprises:
A container main body having a trunk portion in which the flexible portion is formed and a cylindrical opening, and being a main body for accommodating the porous body and the first hydraulic fluid therein;
The porous body and a part of the first hydraulic fluid are inserted into the opening in a state where the porous body and a part of the first hydraulic fluid are put in the whole body part and a part of the opening. A plug for sealing the inside of the container body;
A cover that closes the opening of the container body and seals the remaining portion of the first working fluid in a space defined between the stopper and the self in the opening ;
The plug is
A cylinder device characterized by prohibiting passage of the porous body and allowing passage of air in a state of being inserted into the opening of the container body . The plug is
In a state of being inserted into the opening of the container body, the cylinder device according to claim 1 before Symbol a shall which abolish ban the passage of the first hydraulic fluid. The plug is
3. The cylinder according to claim 1, wherein the cylinder is elastically deformable and stays inside the opening by an elastic force to seal part of the porous body and the first hydraulic fluid. apparatus. The opening of the container body is formed in a cylindrical shape with a constant cross-sectional shape,
The cylinder device according to any one of claims 1 to 3, wherein the plug body has the same cross-sectional shape as a cross-sectional shape of the opening. The housing comprises:
A cylinder body in which the piston slides, and a closing body that closes an end of the cylinder body,
The cylinder device according to any one of claims 1 to 4, wherein the closing body and the lid body of the sealed container are integrally formed.   The cylinder device according to any one of claims 1 to 5, wherein the first hydraulic fluid is water, and the porous body is a hydrophobicized porous body that has been subjected to a hydrophobic treatment.

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