JP2008223837A - Vibration isolation device for suspension and suspension mechanism for automobile using the device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a new structure vibration isolation device for a suspension capable of improving a detection performance of external force acting on wheels of an automobile, and a suspension mechanism for the automobile using the vibration isolation device for the suspension. <P>SOLUTION: A plurality of fluid sealed chambers 30 which have parts of wall surfaces composed of the main body rubber elastic body 16 and have incompressible fluid sealed therein are formed at different positions in circumference directions on at lease one of an outer circumference surface of an inner shaft member 12 and an inner circumference surface of an outer tube member 14 with independent sealed structures formed. A pressure sensor 32 detecting pressure of incompressible fluid sealed in each fluid sealed chamber 30 is provided. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a vibration isolator for a suspension mounted on an automobile and an automobile suspension mechanism using the same, and particularly provides a signal that can be used as a detection signal for control in a system for controlling the running state of the automobile. The present invention relates to a suspension anti-vibration device including a detecting means and an automobile suspension mechanism using the same.

  Conventionally, in order to improve running stability of automobiles, research has been made on suppressing unstable vehicle behavior such as slip by giving a mechanical assistance to a driver's operation. Specifically, for example, an anti-lock braking system (ABS) that suppresses wheel locking during braking has been put into practical use, traction control that suppresses wheel slipping during sudden acceleration, and vehicle behavior stabilization. Vehicle control systems such as vehicle stability control for comprehensive control are being studied.

  By the way, such vehicle control of an automobile is performed using various detection signals corresponding to the running state of the automobile. As a mechanism for detecting such a signal, several devices for detecting an external force (road surface friction force, vertical drag force) acting on a wheel, a road surface friction coefficient, etc. have been proposed. First, in Patent Document 1, for detecting at least one of the inner shaft member and the outer cylinder member constituting the suspension bush that elastically connects the suspension member and the vehicle body, the strain for detecting the strain amount of the member is detected. A suspension anti-vibration device provided with detection means was proposed.

  However, as a result of further experiments and examinations by the applicant, it has been found that there is still room for improvement in the vibration isolator for suspension described in Patent Document 1.

  That is, in the suspension vibration isolator described in Patent Document 1, the strain amount of the inner shaft member and the outer cylinder member is detected by the strain detection means. Since external force is input in the direction perpendicular to the axial direction and the central axis, and further in the twisting direction and the twisting direction, a specific direction can be obtained simply by detecting the strain amount of the member by the strain detecting means. In some cases, it is difficult to improve the detection performance of the external force input to.

JP 2006-138812 A

  Here, the present invention has been made in the background as described above, and the problem to be solved is a novel structure that can improve the detection performance of external force acting on the wheels of an automobile. An object of the present invention is to provide a vibration isolator for a suspension.

  Another object of the present invention is to provide an automobile suspension mechanism using such a suspension vibration isolator.

  Hereinafter, the aspect of this invention made | formed in order to solve such a subject is described. In addition, the component employ | adopted in each aspect as described below is employable by arbitrary combinations as much as possible.

  According to the present invention, an inner shaft member and an outer cylinder member arranged in an extrapolated state spaced apart on the outer peripheral side of the inner shaft member are disposed between opposed surfaces of the inner shaft member and the outer cylinder member in a direction perpendicular to the axis. In the vibration isolator for suspension connected by the disposed main rubber elastic body, at least one of the wall portion is configured by the main rubber elastic body on at least one of the outer peripheral surface of the inner shaft member and the inner peripheral surface of the outer cylindrical member. A plurality of fluid enclosures filled with incompressible fluid are formed at different positions in the circumferential direction with independent sealing structures, and the pressure of the incompressible fluid enclosed in each fluid enclosure is detected. A pressure sensor is provided.

  According to the present invention as described above, there is provided a vibration isolator for a suspension capable of detecting an external force applied to a vehicle wheel from a road surface on a route for transmitting the external force to the vehicle body via the suspension member. The That is, since the external force acting on the wheels is transmitted to the vehicle body via the suspension vibration isolator, all external forces are transmitted to the vehicle body via any suspension vibration isolator. Therefore, depending on the external force to be sought, a suspension vibration isolator that is easily affected by the external force is selected, and the suspension vibration isolator according to the present invention is attached to the vehicle body through the wheels from the road surface. The external force exerted can be detected.

  Here, in the present invention, focusing on the fact that the main rubber elastic body has different deformation modes depending on the direction of the input load, the fluid sealing chamber is formed using the wall portion of the main rubber elastic body to detect the pressure change. I tried to do it. That is, the main rubber elastic body is deformed according to the action of the input load, but depending on the direction of the input load, the elastic deformation at a specific part of the main rubber elastic body changes with compression deformation, tensile deformation, and shear deformation. Along with this, the pressure change mode of the fluid sealing chamber formed therein is also different, such that the pressure increases in compression deformation, the pressure decreases in tensile deformation, and the pressure change hardly occurs in shear deformation. An aspect is shown. Therefore, in consideration of various deformation modes of the main rubber elastic body and the accompanying pressure change mode of the fluid sealing chamber, in the present invention, by appropriately setting the arrangement position of the fluid sealing chamber, a specific direction is obtained. Therefore, it is possible to selectively detect the external force acting on the lens.

  More specifically, when a fluid sealing chamber is formed at a substantially intermediate portion in the axial direction, an external force action in a direction perpendicular to the axis passing through the fluid sealing chamber can be detected as a pressure change. Therefore, it is possible to detect the external force action in the direction perpendicular to the axis with high accuracy while avoiding the influence of the external force action in the axial direction, the twisting direction, and the twisting direction. In this case, if a pair of fluid sealing chambers are provided so as to form a pair facing each other in the direction perpendicular to the axis, the detection accuracy can be improved by observing the pressure changes in both fluid sealing chambers together. It becomes possible to plan. In short, in these pair of fluid sealing chambers, pressures that are opposite in polarity are detected when an external force acts in the direction perpendicular to the axis where the pair of fluid sealing chambers face each other. Further, by providing two pairs of fluid sealing chambers that are opposed to each other in the direction perpendicular to the axis perpendicular to each other, the load input direction in the direction perpendicular to the axis can be specified with higher accuracy. Specifically, for example, when an external force acts in the opposing direction of one pair of fluid sealing chambers, pressure fluctuations in which the positive and negative are opposite are detected in the pair of fluid sealing chambers, the other pair of fluid sealing chambers However, almost no pressure fluctuation is detected. In addition, when a load in the direction perpendicular to the axis is input in an oblique direction that bisects the opposing direction lines of the two pairs of fluid chambers, pressure fluctuations that are opposite in polarity are detected in either of the two pairs of fluid chambers. Is done.

  Furthermore, when the fluid sealing chamber is formed near the end in the axial direction, in addition to being able to detect an external force action in a direction perpendicular to the axis passing through the fluid sealing chamber as a pressure change, The external force action in the twisting direction can also be detected as a pressure change. In addition, the influence by the external force action of a twist direction or an axial direction can be avoided. Further, in this case, they are opposed to each other substantially diagonally so as to be opposed to each other in the direction perpendicular to the axis and to be paired, and to be located near one end in the axial direction and near the other end in the axial direction. By forming a pair of fluid sealing chambers and observing the pressure changes in both fluid sealing chambers together, it is possible to improve the detection accuracy of the external force action in the twisting direction. In short, in these pair of fluid sealing chambers, during the action of the twisting force in the plane perpendicular to the axis where the pair of fluid sealing chambers are opposed to each other by the axial projection of the inner shaft member or the outer cylindrical member, A pressure at which positive and negative are in phase will be detected.

  Note that the pressure sensor is preferably disposed in the fluid-filled chamber by being fixed to, for example, an inner shaft member or an outer cylinder member, thereby enabling the pressure sensor to be supported firmly and stably. Therefore, durability and reliability can be improved.

  In the present invention, for example, the fitting sleeve is attached to the outer peripheral surface of the main rubber elastic body by vulcanization adhesion or the like, and the main rubber elastic body is passed through a window portion penetrating the fitting sleeve. A configuration in which a pocket portion that opens to the outer peripheral surface is formed, the outer cylinder member is externally fixed to the fitting sleeve, and the pocket portion is fluid-tightly covered with the outer cylinder member to form a fluid sealing chamber. Preferably employed.

  Alternatively, similarly, the fitting sleeve is attached to the inner peripheral surface of the main rubber elastic body by vulcanization adhesion or the like, and the surface of the main rubber elastic body is made the inner peripheral surface through a window portion that penetrates the fitting sleeve. On the other hand, the inner shaft member is formed with a pocket-shaped recess at a position corresponding to the window portion, and the inner shaft member is press-fitted and fixed to the fitting sleeve to fit the pocket-shaped recess. A configuration in which the fluid sealing chamber is formed by covering with a main rubber elastic body exposed through the window portion of the sleeve can also be adopted.

  It is also possible to adopt a mode in which an intermediate sleeve is disposed at the radial intermediate portion of the main rubber elastic body and vulcanized and bonded, and a fluid sealing chamber is formed between the radial surfaces of the intermediate sleeve and the outer cylindrical member. is there.

  Further, when such an intermediate sleeve is employed, in the main rubber elastic body, a tick portion extending in the axial direction is formed by opening in the axial end surface between the radially opposing surfaces of the intermediate sleeve and the inner shaft member. It is possible. The straight portion may penetrate in the axial direction or may have a hole shape extending at an appropriate length. By forming such a tick portion, it is possible to set different spring characteristics in the direction perpendicular to the axis. Further, the provision of the intermediate sleeve can reduce the adverse effects caused by the straight portion, and can detect the external force as described above by detecting the pressure of the fluid sealing chamber with high accuracy.

  Further, the present invention employs the vibration isolator for suspension as described above as a suspension bush interposed in a connecting portion of the suspension member of the automobile to the vehicle body, and uses the detection value obtained by the pressure sensor to An automobile suspension mechanism is also characterized in that an external force acting on the wheels from the road surface is obtained.

  Hereinafter, in order to clarify the present invention more specifically, embodiments of the present invention will be described in detail with reference to the drawings.

  First, FIG. 1 and FIG. 2 show a suspension bush 10 as a suspension vibration isolator according to the first embodiment of the present invention. The suspension bush 10 includes an inner cylinder member 12 as an inner shaft member and an inner sleeve 18 as a fitting sleeve connected by a main rubber elastic body 16 and an outer cylinder as an outer cylinder member with respect to the inner sleeve 18. The metal fitting 14 is fixedly fitted.

  More specifically, the inner cylinder fitting 12 has a substantially cylindrical shape with a small diameter. On the other hand, the inner sleeve 18 has a thin cylindrical shape.

  Accordingly, the inner sleeve 18 of the present embodiment is formed with a plurality of (four in the present embodiment) opening windows 22 as window portions. In particular, in the present embodiment, each of the opening windows 22 has an inner sleeve. In the circumferential direction around the central axis of 18, it is formed with a size smaller than the region of the central angle of 45 degrees, and its circumferential length is sufficiently shorter than the entire circumference of the inner cylinder fitting 12. The axial length is sufficiently shorter than the axial length of the inner sleeve 18.

  Further, in the present embodiment, these four opening windows 22 are separated from each other in the circumferential direction of the inner sleeve 18 in the circumferential projection of the two adjacent opening windows 22, 22 in the axial projection of the inner sleeve 18. It is formed so that it may be about 1/4.

  That is, in the present embodiment, in the projection in the central axis direction of the inner sleeve 18, the two opening windows 22 a and 22 b out of the four opening windows 22 are opposed to each other in the radial direction across the central axis of the inner sleeve 18. While making a pair, the remaining two opening windows 22c and 22d are opposed to each other in the radial direction across the central axis of the inner sleeve 18 in a direction orthogonal to the facing direction of the pair of opening windows 22a and 22b. They are making a pair.

  In other words, in the present embodiment, the four opening windows 22 are formed at positions where the circumferential positions do not overlap in the projection in the central axis direction of the inner sleeve 18.

  Furthermore, in the present embodiment, the four opening windows 22 are respectively formed at the same position in the axial direction of the inner sleeve 18. In particular, in the present embodiment, each of the four opening windows 22 is the inner sleeve 18. It is formed at the center in the axial direction.

  On the other hand, the outer cylinder fitting 14 of the present embodiment has a thin cylindrical shape, and the inner diameter dimension thereof is larger than the outer diameter dimension of the inner sleeve 18. In addition, a seal rubber 24 is attached to the inner peripheral surface of the outer cylinder fitting 14 over substantially the entire surface. Then, when the outer cylinder fitting 14 is fitted and fixed to the inner sleeve 18, the seal rubber 24 is sandwiched between the outer peripheral surface of the inner sleeve 18 and the inner peripheral surface of the outer cylinder fitting 14 in a compressed state. ing. In the present embodiment, both ends in the axial direction of the outer tube fitting 14 fitted and fixed to the inner sleeve 18 are bent inward in the radial direction, and are brought into contact with the axial end surface of the inner sleeve 18. Thereby, the relative displacement in the axial direction of the inner sleeve 18 and the outer cylinder fitting 14 is prevented.

  Therefore, in the present embodiment, in the state in which the outer cylinder fitting 14 is fitted and fixed to the inner sleeve 18 as described above, the opening window 22 formed in the inner sleeve 18 on the inner peripheral surface of the outer cylinder fitting 14 is provided. The seal rubber 24 is not attached to the corresponding position, and the inner peripheral surface of the outer tube metal fitting 14 is exposed. That is, in the present embodiment, an opening 26 is formed at a position corresponding to the opening window 22 of the inner sleeve 18 in the seal rubber 24, and the inner peripheral surface of the outer cylindrical metal member 14 is exposed through the opening 26. It has become.

  Although not clearly shown in the drawings, rib protrusions are provided on the entire periphery of the opening 26 of the seal rubber 24, and the outer tube fitting 14 is fitted and fixed to the inner sleeve 18. As a result of the rib protrusion being crushed, the sealing performance at the peripheral edge of the opening window 22 formed in the inner sleeve 18 is ensured between the opposing surfaces of the inner sleeve 18 and the outer tube fitting 14.

  Further, the outer cylinder fitting 14 fitted and fixed to the inner cylinder fitting 12 and the inner sleeve 18 are arranged on the same central axis and are spaced apart from each other in the radial direction perpendicular to the axis. At that time, the axial center of the outer tube fitting 14 fitted and fixed to the inner sleeve 12 and the inner sleeve 18 are made to coincide with each other, and the inner tube fitting 12 protrudes from one axial end of the outer tube fitting 14 in the axial direction. The amount and the protruding amount of the inner cylinder fitting 12 from the other opening end in the axial direction of the outer cylinder fitting 14 are the same. That is, the inner cylinder fitting 12 and the outer cylinder fitting 14 are arranged in the positional relationship as described above, thereby having a common central axis and a common axial center.

  In addition, the outer peripheral surface of the inner cylinder fitting 12 and the outer cylinder fitting 14 are externally attached in a state where the outer cylinder fitting 14 fitted and fixed to the inner sleeve 18 and the inner sleeve 18 are arranged in the above-described positional relationship. A main rubber elastic body 16 having a substantially cylindrical shape as a whole is interposed between the inner peripheral surface of the inner sleeve 18 that is fitted and fixed, and the main rubber elastic body with respect to the outer peripheral surface of the inner cylinder fitting 12. The inner peripheral surface of 16 is vulcanized and bonded, and the outer peripheral surface of the main rubber elastic body 16 is vulcanized and bonded to the inner peripheral surface of the inner sleeve 18. Actually, the outer fitting 14 is fitted and fixed to the inner sleeve 18 after an integrally vulcanized molded product of the main rubber elastic body 16 including the inner cylindrical fitting 12 and the inner sleeve 18 is manufactured. This is done by extrapolating the outer tube fitting 14 to the inner sleeve 18 of the integrally vulcanized molded product of the elastic body 16 and reducing the diameter.

  Accordingly, the main rubber elastic body 16 of the present embodiment has a recess as a pocket portion that opens in the same shape and size as the opening window 22 at a position corresponding to the opening window 22 of the inner sleeve 18 on the outer peripheral surface thereof. In particular, in the present embodiment, the depth direction of the recess 28 is sufficiently smaller than the dimension perpendicular to the axis of the main rubber elastic body 16.

  Then, the main rubber elastic body 16 is vulcanized and bonded to the inner sleeve 18 as described above, whereby each recess 28 provided in the main rubber elastic body 16 is opened to the outer peripheral surface of the inner sleeve 18 through the opening window 22. It has been. Further, the outer cylinder fitting 14 is externally fitted and fixed to the inner sleeve 18 having the recess 28 opened to the outer peripheral surface through the opening window 22 in this manner, so that the opening (opening window 22) of the recess 28 is formed. The outer cylinder fitting 14 is covered with fluid tightly.

  As a result, a liquid as an incompressible fluid is sealed between the bottom surface of the recess 28 and the inner peripheral surface of the outer cylindrical metal member 14 which are opposed to each other through the opening window 22 formed in the inner sleeve 18. A fluid sealing chamber 30 is formed in which a part of the wall part is formed of the main rubber elastic body 16 and another part of the wall part is formed of the outer tube fitting 14.

  In other words, in the present embodiment, the four fluid enclosures 30 are each provided on the inner peripheral surface of the outer cylinder fitting 14 and have an independent sealing structure. Further, in the present embodiment, in the projection in the central axis direction of the inner cylindrical metal fitting 12, the pair of fluid sealing chambers 30a and 30b that are opposed to each other in the radial direction across the central axis of the inner cylindrical metal fitting 12, respectively, A pair of fluid sealing chambers 30c and 30d formed in the center of the cylindrical metal member 12 in the axial direction and opposed to each other in a direction orthogonal to the opposing direction of the pair of fluid sealing chambers 30a and 30b are also respectively provided with the inner cylindrical metal fittings. 12 are formed in the center in the axial direction. Each fluid sealing chamber 30 has a circumferential length that is sufficiently shorter than the circumferential length of the inner cylinder fitting 12, and an axial length that is sufficiently larger than the axial length of the outer cylinder fitting 14. Furthermore, the length in the direction perpendicular to the axis is sufficiently shorter than the length in the direction perpendicular to the axis of the main rubber elastic body 16, and as a result, the volume of each fluid sealing chamber 30 is reduced. The volume of the rubber elastic body 16 is sufficiently small.

  In this case, as the liquid sealed in each fluid sealing chamber 30, for example, an incompressible liquid such as water, alkylene glycol, polyalkylene glycol, or silicone oil is employed.

  Each fluid sealing chamber 30 is provided with a pressure sensor 32. In particular, in the present embodiment, the pressure sensor is used with respect to the outer peripheral surface of the outer cylindrical metal member 14 constituting a part of the wall surface of the fluid sealing chamber 30. 32 is fixed. The pressure sensor 32 is constituted by a semiconductor pressure sensor, a piezoelectric pressure sensor, or the like.

  The suspension bush 10 having such a structure is attached to a suspension component 34 as a suspension member including a suspension link, a suspension rod, and the like, and is used for a suspension mechanism.

  More specifically, as shown in FIG. 2, the suspension bushing is inserted into the fitting hole 40 formed in the bushing mounting portion 38 formed at the end of the suspension arm 36 constituting the suspension component 34. 10 is inserted in an inserted state. The bush mounting portion 38 has a substantially cylindrical shape, and its inner diameter is slightly smaller than the outer diameter of the suspension bush 10, and the suspension bush 10 is press-fitted into the bush mounting portion 38. The suspension bush 10 is fixedly attached to the suspension component 34.

  Therefore, in the present embodiment, the four fluid sealing chambers 30 formed in two radial directions substantially orthogonal to the central axis of the inner cylinder fitting 12 with the suspension bush 10 attached to the suspension component 34 are The two fluid enclosures 30a and 30b are opposed to each other in the longitudinal direction of the vehicle, while the remaining two fluid enclosures 30c and 30d are opposed to each other in the lateral direction of the vehicle.

  Further, a fixing rod (not shown) protruding from the vehicle body (not shown) is inserted into the inner cylinder fitting 12 so that the inner cylinder fitting 12 is fixed to the vehicle body by bolts, welding, or the like. It has become.

  In this manner, the inner cylinder fitting 12 is fixed to the vehicle body (not shown), and the outer cylinder fitting 14 is fixed to the suspension component 34, whereby the vehicle body and the suspension component 34 (not shown) are interposed via the suspension bush 10. It is elastically connected.

  In the present embodiment, a pressure change based on an acting force exerted on the suspension bushing 10 from the wheel via the suspension component 34 to the wheel is detected by the pressure sensor 32, and the detection of the pressure sensor 32 is performed. The value is directly or amplified by an appropriate amplifier, and further subjected to an appropriate electrical process corresponding to a calculation process, for example, an anti-lock braking system, traction control, vehicle stability control, etc. It will be used as a control signal at the time.

  If the suspension mechanism as described above is employed, two fluid sealing chambers 30a and 30b out of the four fluid sealing chambers 30 formed in the suspension bush 10 are opposed to each other in the longitudinal direction of the vehicle, and the remaining two Since the two fluid sealing chambers 30c and 30d are opposed to each other in the left-right direction of the vehicle, it is possible to advantageously detect a change in hydraulic pressure according to an external force acting in a specific direction with respect to the wheel. On the other hand, it is possible to reliably estimate the external force acting in a specific direction.

  Therefore, in this embodiment, since the four fluid sealing chambers 30 are all formed at the center in the axial direction of the outer cylinder fitting 14, the external force acting in the twisting direction, the twisting direction, and further in the axial direction. For example, it is possible to advantageously detect a change in hydraulic pressure in the fluid sealing chamber 30 that is generated based on an external force acting in the front-rear and left-right directions of the vehicle, and as a result, acts on the wheels. The external force can be estimated with high accuracy in the front-rear and left-right directions of the vehicle, which is the direction that needs to be estimated.

  Moreover, in this embodiment, since the outer cylinder metal fitting 14 is located near a wheel compared with the inner cylinder metal fitting 12, the external force which acted on the wheel will act directly. Therefore, the fluid pressure change in the fluid sealing chamber 30 in which a part of the wall portion is constituted by the outer cylinder fitting 14 is highly correlated with the external force acting on the wheel, and the external force applied to the wheel can be estimated with high accuracy. It becomes possible.

  Furthermore, in the present embodiment, since the liquid is sealed in each fluid sealing chamber 30, it is possible to detect advantageously the change in the internal pressure of the fluid sealing chamber 30.

  Next, a suspension bush 42 as a suspension vibration isolator according to a second embodiment of the present invention will be described with reference to FIGS. 3 and 4. In the description of the second embodiment, the third embodiment described later, and the fourth embodiment, members and parts having the same structure as that of the first embodiment are shown in FIG. Detailed description thereof will be omitted by attaching the same reference numerals as those of the embodiment.

  As shown in FIGS. 3 and 4, the suspension bush 42 of the present embodiment is different from the suspension bush (10) of the first embodiment in the number and formation positions of the fluid enclosure chambers 30. .

  More specifically, in the case of this embodiment, two fluid enclosures 30 are formed. In particular, in this embodiment, one of these two fluid enclosures 30 is one axial end side of the outer cylinder fitting 14. The other is formed on the other end side in the axial direction of the outer cylinder fitting 14. In other words, the two fluid sealing chambers 30 are formed so as to make a pair on the opposite sides in the axial direction of the outer cylinder fitting 14.

  Further, in the present embodiment, these two fluid sealing chambers 30 are positioned at an appropriate distance in the circumferential direction in the projection in the central axis direction of the inner cylinder fitting 12. In other words, the two fluid sealing chambers 30 of the present embodiment are formed at positions that do not overlap in the projection in the central axis direction of the inner cylinder fitting 12.

  In particular, in the present embodiment, these two fluid sealing chambers 30 are formed at positions separated from each other by about 1/4 in the circumferential direction around the central axis of the inner cylinder fitting 12 in the projection in the center axis direction of the inner cylinder fitting 12. Has been.

  As shown in FIG. 4, the suspension bush 42 of this embodiment is also attached to the bush attachment portion 38 of the suspension component 34 and used in the suspension mechanism.

  Accordingly, in the present embodiment, when the suspension bushing 42 is attached to the suspension component 34, the change in the hydraulic pressure in one of the fluid sealing chambers 30 is detected by the pressure sensor 32, thereby inputting the vehicle in the front-rear direction. While the external force can be detected, the external force input in the left-right direction of the vehicle can be detected by detecting the change in the hydraulic pressure of the other fluid sealing chamber 30 with the pressure sensor 32.

  Also in the suspension mechanism using the suspension bush 42 of the present embodiment, each fluid sealing chamber 30 is formed at a position where an external force in a specific direction can be detected. Therefore, the same effect as in the first embodiment can be obtained. Can be obtained.

  Further, in the present embodiment, the two fluid sealing chambers 30 are formed at positions separated by approximately ¼ circumference in the circumferential direction around the central axis of the outer cylinder fitting 14 in the projection in the center axis direction of the inner cylinder fitting 12. In addition, one of the two fluid sealing chambers 30 is formed on one side in the axial direction of the outer cylinder fitting 14 while the other is formed on the other side in the axial direction of the outer cylinder fitting 14. It is less susceptible to the influence of external forces acting in the twisting direction and the axial direction, and it is possible to advantageously detect a change in the hydraulic pressure of the fluid sealing chamber 30 generated based on the external force acting in the direction perpendicular to the axis and the twisting direction. As a result, the external force acting on the wheel can be estimated with high accuracy in the front-rear and left-right directions and the turning direction of the vehicle as the direction perpendicular to the axis, which is the direction that needs to be estimated.

  Next, a suspension bush 44 as a suspension vibration isolator according to a third embodiment of the present invention will be described with reference to FIGS.

  The suspension bush 44 of the present embodiment is provided with a metal sleeve 46 as an intermediate sleeve spaced apart on the outer peripheral side of the inner cylindrical metal member 12, and the inner cylindrical metal member 12 and the metal sleeve 46 are The inner cylindrical metal member 12 and the metal sleeve 46 are connected by an inner rubber elastic body 48 disposed between opposing surfaces in the direction perpendicular to the axis. Specifically, in the case of this embodiment, the outer peripheral surface of the inner cylindrical metal member 12 and the inner peripheral surface of the inner rubber elastic body 48 are vulcanized and bonded, and the inner peripheral surface of the metal sleeve 46 and the inner rubber elastic body 48. The outer peripheral surface is vulcanized and bonded, and the inner cylinder fitting 12 and the metal sleeve 46 are connected by the inner rubber elastic body 48. In addition, the inner rubber elastic body 48 is formed with a pair of straight portions 50 and 50 so as to be opposed to each other in one radial direction with the inner cylinder fitting 12 interposed therebetween.

  Furthermore, in the present embodiment, the outer cylinder fitting 14 is arranged in an extrapolated state so as to be separated from the outer peripheral side of the metal sleeve 46, and the metal sleeve 46 and the outer cylinder fitting 14 are connected to the metal sleeve 46 and the outer cylinder fitting. 14 are connected by outer rubber elastic bodies 52 disposed between opposing surfaces in the direction perpendicular to the axis. Specifically, in the case of this embodiment, the inner peripheral surface of the outer rubber elastic body 52 is vulcanized and bonded to the outer peripheral surface of the metal sleeve 46, and vulcanized and bonded to the outer peripheral surface of the metal sleeve 46 in this way. The outer sleeve elastic member 52 is fitted and fixed by inserting the outer tube fitting 14 into the outer rubber elastic member 52 and drawing, so that the metal sleeve 46 and the outer tube fitting 14 are fixed by the outer rubber elastic member 52. It is connected. In this case, the outer rubber elastic body 52 has a thickness dimension (dimension perpendicular to the axis) that can change the hydraulic pressure in the fluid sealing chamber described later.

  As is apparent from this, in the present embodiment, the metal sleeve 46 is positioned between the opposing surfaces of the inner cylinder fitting 12 and the outer cylinder fitting 14 in the direction perpendicular to the axis, and the inner rubber elastic body 48 and The outer rubber elastic body 52 constitutes a main rubber elastic body that connects the inner cylinder fitting 12 and the outer cylinder fitting 14.

  In addition, the outer rubber elastic body 52 is formed with a plurality of openings (four in the present embodiment) that expose the outer peripheral surface of the metal sleeve 46 to the outside. In particular, in the present embodiment, these four openings are formed. The portion 54 is formed at the center in the axial direction of the outer rubber elastic body 52 so that the circumferential separation distances are equal.

  Therefore, in the present embodiment, in the projection in the central axis direction of the inner cylindrical metal member 12, two openings that are opposed to each other in the radial direction across the central axis of the inner cylindrical metal member 12 among these four openings 54. The opposing direction of the portions 54a and 54b is made to coincide with the opposing direction of the pair of straight portions 50 and 50 formed in the inner rubber elastic body 48, and the remaining two openings 54c and 54d are a pair of straight portions. 50 and 50 are opposed to each other in a direction perpendicular to the opposing direction.

  The outer rubber member 52 is fixed to the outer rubber elastic body 52 in which the outer cylindrical metal fitting 14 is extrapolated and subjected to drawing or the like with respect to the outer rubber elastic body 52 in which the opening 54 is formed. The formed opening 54 is covered with the outer cylinder fitting 14, and as a result, the outer peripheral surface of the metal sleeve 46 and the inner circumference of the outer cylinder fitting 14 that are opposed to each other through the opening 54 of the outer rubber elastic body 52. A liquid as an incompressible fluid is sealed between the surface and a part of the wall part is configured by the outer rubber elastic body 52, and the other part of the wall part is the outer cylindrical fitting 14. A configured fluid sealing chamber 56 is formed.

  That is, in this embodiment, in the projection in the central axis direction of the inner cylinder fitting 12, the pair of fluid sealing chambers 56a and 56b that are opposed to each other in the radial direction across the center axis of the inner cylinder fitting 12 are respectively A pair of fluid sealing chambers 56c and 56d that are formed at the center in the axial direction of the cylindrical fitting 12 and are opposed to each other in a direction orthogonal to the opposing direction of the pair of fluid sealing chambers 56a and 56b are also respectively provided in the inner cylindrical fitting. 12 are formed in the center in the axial direction.

  Further, in the present embodiment, in the projection in the central axis direction of the inner cylindrical metal fitting 12, the facing direction of the pair of fluid sealing chambers 56a and 56b is made to coincide with the facing direction of the pair of straight portions 50 and 50, while the rest The opposing direction of the pair of fluid sealing chambers 56c, 56d is orthogonal to the opposing direction of the pair of straight portions 50, 50.

  Each fluid sealing chamber 56 accommodates and arranges a pressure sensor 32 fixed to the inner peripheral surface of the outer cylinder fitting 14.

  As shown in FIG. 6, the suspension bush 44 of this embodiment is also attached to the bush attachment portion 38 of the suspension component 34 and used for the suspension mechanism.

  Therefore, in the present embodiment, in a state where the suspension bush 44 is attached to the suspension component 34, the facing direction of the pair of straight portions 50, 50, that is, the facing direction of the pair of fluid sealing chambers 56a, 56b is On the other hand, the opposing direction of the pair of fluid sealing chambers 56c and 56d is the front-rear direction of the vehicle. As a result, the pressure sensor 32 detects a change in hydraulic pressure in the fluid sealing chamber 56. An external force acting in a specific direction, for example, an external force input in the front-rear and left-right directions of the vehicle can be detected.

  Also in the suspension mechanism using the suspension bush 44 of the present embodiment, each fluid sealing chamber 56 is formed at a position where an external force in a specific direction can be detected. Can be obtained.

  Further, in the present embodiment, since the pair of fluid sealing chambers 56a and 56b are opposed to each other in the facing direction of the pair of straight portions 50 and 50, the suspension bush in which the straight portion 50 is formed on the main rubber elastic body. Also in the suspension using the external force, it is possible to estimate the external force input in the opposing direction of the pair of straight portions 50 and 50.

  Next, a suspension bush 60 as a suspension vibration isolator according to a fourth embodiment of the present invention will be described with reference to FIG.

  In the suspension bush 60 of the present embodiment, one of the pair of fluid sealing chambers 30, 30 that are opposed to each other in one radial direction across the inner cylinder fitting 12 in the projection in the central axis direction of the inner cylinder fitting 12 is the outer cylinder fitting. 14 is formed on one side in the axial direction, and the other is formed on the other side in the axial direction of the outer tube fitting 14. In other words, the fluid sealing chambers 30 are formed so as to make a pair by being positioned on opposite sides in the axial direction of the inner cylinder fitting 12.

  And in such a suspension bush 60, it becomes possible to improve the detection accuracy of the external force which acts in the turning direction.

  As mentioned above, although several embodiment of this invention has been explained in full detail, these are illustrations to the last, Comprising: This invention is not limited at all by the specific description in this embodiment. .

  For example, it is possible to form two or more fluid sealing chambers at positions that overlap when projected in the central axis direction of the inner shaft member. Moreover, it is also possible to form the fluid sealing chamber in which a part of the wall portion is constituted by the inner shaft member.

  Furthermore, in the third embodiment, the outer cylinder fitting 14 may be externally fixed to the fitting sleeve.

  In addition, although not listed one by one, the present invention can be implemented in a mode with various changes, modifications, improvements, and the like based on the knowledge of those skilled in the art. It goes without saying that all are included in the scope of the present invention without departing from the spirit of the invention.

It is a longitudinal cross-sectional view which shows the suspension bush of 1st embodiment of this invention, Comprising: The longitudinal cross-sectional view of the direction corresponded to the II direction of FIG. FIG. 2 is a cross-sectional view showing a state in which the suspension bush is attached to a suspension component, and a cross-sectional view in a direction corresponding to the II-II direction in FIG. 1. It is a longitudinal cross-sectional view which shows the suspension bush of 2nd embodiment of this invention, Comprising: The longitudinal cross-sectional view of the direction corresponded to the III-III direction of FIG. FIG. 4 is a cross-sectional view showing a state in which the suspension bush is attached to a suspension component, and is a cross-sectional view in a direction corresponding to the IV-IV direction in FIG. 3. It is a longitudinal cross-sectional view which shows the suspension bush of 3rd embodiment of this invention, Comprising: The longitudinal cross-sectional view of the direction corresponded to the VV direction of FIG. FIG. 6 is a cross-sectional view showing a state in which the suspension bush is attached to a suspension component, and is a cross-sectional view in a direction corresponding to the VI-VI direction of FIG. 5. The longitudinal cross-sectional view which shows the suspension bush of 4th embodiment of this invention.

Explanation of symbols

10: Suspension bush, 12: Inner cylinder fitting, 14: Outer cylinder fitting, 16: Rubber elastic body of main body, 30: Fluid sealing chamber, 32: Pressure sensor

Claims (9)

An inner shaft member and an outer cylinder member that is spaced apart from the outer peripheral side of the inner shaft member and disposed in an extrapolated state are disposed between opposing surfaces of the inner shaft member and the outer cylinder member in a direction perpendicular to the axis. In the vibration isolator for the suspension connected by the main rubber elastic body,
On at least one of the outer peripheral surface of the inner shaft member and the inner peripheral surface of the outer cylinder member, a fluid sealing chamber in which a part of the wall portion is constituted by the main rubber elastic body and in which an incompressible fluid is sealed The suspension protection device is characterized in that a plurality of independent sealing structures are formed at different positions in the circumferential direction, and a pressure sensor for detecting the pressure of the incompressible fluid sealed in each fluid sealing chamber is provided. Shaker.   The vibration isolator for a suspension according to claim 1, wherein the fluid sealing chamber is formed so as to be opposed to each other with a central axis of the inner shaft member or the outer cylinder member interposed therebetween.   The vibration isolator for a suspension according to claim 1 or 2, wherein the fluid sealing chamber is formed at a position separated by 90 degrees in a circumferential direction around a central axis of the inner shaft member or the outer cylinder member.   The suspension according to any one of claims 1 to 3, wherein the fluid sealing chamber is formed so as to be paired by being positioned on opposite sides in the axial direction of the inner shaft member or the outer cylinder member. Anti-vibration device.   The suspension vibration isolator according to any one of claims 1 to 4, wherein the pressure sensor is fixed to the inner shaft member or the outer cylinder member in the fluid sealing chamber.   A fitting sleeve is attached to the outer peripheral surface of the main rubber elastic body, and a pocket portion that opens to the outer peripheral surface is formed in the main rubber elastic body through a window portion penetrating the fitting sleeve. 6. The fluid sealing chamber is formed by the outer cylinder member being fitted and fixed to the fitting sleeve, and the pocket portion being covered with the outer cylinder member. A vibration isolator for a suspension according to claim 1.   An intermediate sleeve is disposed and vulcanized and bonded to a radially intermediate portion of the main rubber elastic body, and the fluid sealing chamber is formed between the intermediate sleeve and the radially opposing surface of the outer cylinder member. The suspension vibration isolator according to any one of claims 1 to 6.   8. The suspension body according to claim 7, wherein the main rubber elastic body is formed with a tickling portion that opens in an axial end surface and extends in an axial direction between radially opposed surfaces of the intermediate sleeve and the inner shaft member. Anti-vibration device.   The suspension vibration isolator according to any one of claims 1 to 8 is used as a suspension bush interposed in a connection portion of a suspension member of an automobile to a vehicle body, and a detection value obtained by the pressure sensor is used. An automobile suspension mechanism characterized in that an external force acting on a vehicle wheel from a road surface is obtained.

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