JP3763024B1 - Liquid-filled vibration isolator - Google Patents

Abstract

In a liquid-filled vibration isolator provided with a sub-orifice having a rubber valve, a sufficient orifice length for a main orifice is ensured.
An intermediate cylinder 32 positioned between inner and outer cylinders 12 and 14 is constituted by fitting peripheral walls 34 and 36 at both ends and connecting walls 38 and 40 between them, and a pressure contact portion 44 against the outer cylinder on the outer surface side of the connecting wall. , 46 are provided. Fitting recesses 48 and 54 are provided in the pressure contact portion, main orifice forming members 60 and 70 are arranged in the first liquid chamber and the second liquid chamber, and fitting protrusions 66, 68, 76, 78 is fitted into the corresponding fitting recess, thereby forming the main orifice 22 for communicating the first liquid chamber and the second liquid chamber. The seal rubber 100 is provided at the circumferential end 38C of the connecting wall, and the circumferential end portions 60A and 70A of the main orifice forming member are brought into pressure contact with each other. Prevent liquid leakage between the two.
[Selection] FIG.

Description

  The present invention relates to a liquid-filled vibration isolator.

  Conventionally, as a liquid-filled vibration isolator, the following Patent Documents 1 and 2 include an inner cylinder, an outer cylinder, a vibration isolating base composed of a rubber-like elastic body interposed between both cylinders, an intermediate cylinder, and an inner cylinder. There is disclosed a bush type vibration isolator including a first liquid chamber and a second liquid chamber provided on both sides of the main body, and a main orifice for communicating both liquid chambers. In this vibration isolator, the intermediate cylinder is positioned between the pair of ring-shaped fitting peripheral walls on both ends in the axial direction with which the outer cylinder is fitted, and the axis of the intermediate cylinder, and the pair of fitting peripheral walls The main orifice is formed by forming an orifice groove in a rubber portion provided on the outer peripheral surface side of the connection wall and covering this with an outer cylinder.

  Further, in Patent Document 3 below, in the liquid-filled vibration isolator having the above-described structure, a liquid is circulated only from the first liquid chamber side to the second liquid chamber side via the first rubber valve. And a second sub-orifice for allowing liquid to flow only from the second liquid chamber side to the first liquid chamber side via the second rubber valve, and the first sub-orifice on the outer peripheral surface side of the connecting wall A second sub-orifice is disclosed. In this liquid-filled vibration isolator, when the hydraulic pressure difference between the first liquid chamber and the second liquid chamber becomes a set value and becomes a set value, the first rubber valve or the second rubber valve is elastically deformed and opened. When the liquid flows through the first sub-orifice or the second sub-orifice, the hydraulic pressure difference is alleviated.

In the above conventional liquid-filled vibration isolator, each of the main orifices is simply formed by forming an orifice groove in a rubber portion provided on the outer peripheral surface side of the connecting wall and covering this with an outer cylinder. It was.
JP 2003-184941 A JP 2003-83389 A WO 03/033936 A1

  In the conventional structure described above, the main orifice is provided in the rubber portion provided on the outer peripheral surface side of the connecting wall of the intermediate cylinder, so that it is difficult to ensure a sufficient orifice length corresponding to the required vibration isolation characteristics. It was. In particular, when the first sub-orifice and the second sub-orifice are formed on the outer peripheral surface of the connecting wall as well as the first sub-orifice and the second sub-orifice on the outer peripheral surface of the connection wall as in the above-described vibration isolator of Patent Document 3, the main orifice is formed. Sufficient space cannot be secured.

  The present invention has been made in view of the above points, and an object of the present invention is to provide a liquid-filled vibration isolator capable of ensuring a sufficient orifice length for the main orifice.

  A liquid-filled vibration isolator according to the present invention includes an inner cylinder, an outer cylinder that surrounds the inner cylinder in an axis-parallel manner, and a vibration-damping base that includes a rubber-like elastic body interposed between the inner cylinder and the outer cylinder, An intermediate cylinder positioned between the inner cylinder and the outer cylinder, a first liquid chamber and a second liquid chamber positioned with the inner cylinder interposed therebetween, and a main orifice that communicates the first liquid chamber and the second liquid chamber. Prepare. The intermediate cylinder is positioned between a pair of ring-shaped fitting peripheral walls on both end sides in the axial direction to which the outer cylinder is fitted, and the inner cylinder, and is positioned radially inward from the fitting peripheral wall. A pair of connecting walls that connect the pair of fitting peripheral walls, and the anti-vibration base couples an inner surface of the pair of connecting walls and an outer peripheral surface of the inner cylinder facing the inner surface. The first liquid chamber and the second liquid chamber are partitioned in the circumferential direction, and an end wall made of a rubber-like elastic body is provided between the pair of fitting peripheral walls and the inner cylinder, The end walls form chamber walls at the axial ends of the first liquid chamber and the second liquid chamber. In addition, a first pressure contact portion made of a rubber-like elastic body that is in pressure contact with the inner peripheral surface of the outer cylinder is provided on the outer surface side of one of the connection walls, and a first fitting recess is provided in the first pressure contact portion, A second pressure contact portion made of a rubber-like elastic body that is in pressure contact with the inner peripheral surface of the outer cylinder is provided on the outer surface side of the other connecting wall, and a second fitting recess is provided in the second pressure contact portion. In the first liquid chamber, a first main orifice forming member having a first main orifice groove communicating with the first liquid chamber through the first opening on the outer peripheral surface is disposed. Fitting protrusions project from both ends in the circumferential direction, and the first main orifice groove is opened outward in the circumferential direction at one of the fitting protrusions. By fitting the one fitting projection into the first fitting recess and the other fitting projection into the second fitting recess, the first press contact on both sides in the first liquid chamber It arrange | positions in the state spanned between the part and the 2nd press-contact part. Further, the outer peripheral surface of the first main orifice forming member is in pressure contact with the inner peripheral surface of the outer cylinder, and the first main orifice groove is communicated with the second liquid chamber side in the first press contact portion, thereby the main orifice. Is formed. In addition, a seal rubber is provided at a circumferential end on the first liquid chamber side of the one connecting wall provided with the first fitting recess, and a circumferential end of the first main orifice forming member with respect to the seal rubber Is prevented from leaking from the first liquid chamber to the space between the one fitting protrusion and the first fitting recess.

  According to this configuration, since the main orifice is formed by the first main orifice forming member mounted inside the first liquid chamber, a sufficient orifice length for the main orifice can be ensured. The liquid flow action by the orifice can be effectively exhibited. Moreover, this 1st main orifice formation member fits the fitting protrusion of both ends to the 1st and 2nd fitting recessed part provided in the 1st and 2nd press-contact part of the outer surface side of a connection wall. Since it is arranged in the first liquid chamber, assembly work is also easy.

  By the way, in such a structure in which the main orifice is formed by fitting the fitting protrusion of the main orifice forming member into the first fitting recess, liquid leakage occurs between the fitting protrusion and the first fitting recess. May occur. When such a liquid leak occurs, a predetermined attenuation by the main orifice cannot be obtained. On the other hand, according to the present invention, as described above, the seal rubber is provided at the circumferential end of one of the connecting walls, and the seal rubber is compressed and sealed by the first main orifice forming member. Thus, the predetermined attenuation effect by the main orifice can be reliably exhibited.

  In the liquid filled type vibration damping device of the present invention, a gap is provided between the circumferential end of one of the connecting walls and the circumferential end of the first main orifice forming member, and the seal rubber is placed in the gap. It is preferable that the gap is held in a state where the outer cylinder is compressed and held, and the outer cylinder is press-fitted into the mounting hole of the mounted member. This type of liquid-filled vibration isolator is attached by press-fitting an outer cylinder into a mounting hole portion of a member to be mounted. By such press-fitting, the circumferential end of the one connecting wall and the first main orifice forming member If the end in the circumferential direction comes into contact, the seal rubber may break and liquid leakage may occur from there. On the other hand, by securing the gap where the seal rubber is interposed even during press-fitting as described above, it is possible to eliminate the rubber breakage and prevent the liquid leakage more reliably.

  In the liquid-filled vibration isolator of the present invention, an inner stopper that protrudes radially outward from the inner cylinder side is provided in the first liquid chamber, and the first main orifice forming member faces the inner stopper. Then, an outer stopper protruding radially inward may be provided.

  In the case of providing a stopper that limits the relative displacement of the inner and outer cylinders within a predetermined range, it can be configured only by a stopper that protrudes radially outward from the inner cylinder side as in Patent Documents 1 to 3 above. However, when the stopper is formed only from the inner cylinder side, the stopper comes into contact with the end wall and is damaged when displaced in a twisting direction in which the axis of the outer cylinder is inclined with respect to the axis of the inner cylinder. There is a fear. On the other hand, as described above, the stopper is divided into the inner stopper from the inner cylinder side and the outer stopper from the main orifice forming member, thereby preventing the end wall from being damaged at the time of displacement in the twisting direction. Can do. In other words, according to the present invention, the member for forming the main orifice also acts as a stopper, thereby ensuring the orifice length for the main orifice without increasing the number of parts and the end wall of the stopper. Damage can be prevented.

  In the liquid-sealed vibration isolator of the present invention, a main orifice forming member can be provided in the second liquid chamber as well as the first liquid chamber. That is, a second main orifice forming member provided on the outer peripheral surface with a second main orifice groove communicating with the second liquid chamber through the second opening may be disposed in the second liquid chamber. In this case, fitting protrusions are provided at both ends in the circumferential direction of the second main orifice forming member, and the second main orifice groove is opened outward in the circumferential direction at one of the fitting protrusions. The second main orifice forming member is configured to fit the one fitting projection into the first fitting recess and the other fitting projection into the second fitting recess, respectively. The two liquid chambers are arranged in a state of being spanned between the first press contact portion and the second press contact portion on both sides. The outer peripheral surface of the second main orifice forming member is pressed against the inner peripheral surface of the outer cylinder, and the first main orifice groove and the second main orifice groove are connected in communication at the first press contact portion. The main orifice is formed. Further, a seal rubber is provided at a circumferential end on the second liquid chamber side of the one connecting wall provided with the first fitting recess, and a circumferential end of the second main orifice forming member with respect to the seal rubber It is preferable that liquid leakage from the second liquid chamber to the space between the one fitting protrusion and the first fitting recess is prevented by press-contacting. As described above, by mounting the second main orifice forming member as well, the orifice length for the main orifice can be secured more sufficiently, and the liquid flow action by the main orifice can be effectively exhibited.

  The liquid-filled vibration isolator of the present invention includes a first sub-orifice for allowing liquid to flow only from the first liquid chamber side to the second liquid chamber side via the first rubber valve, and a second via the second rubber valve. And a second sub-orifice that allows the liquid to flow only from the liquid chamber side to the first liquid chamber side. In this case, a first sub-orifice groove extending in the circumferential direction is provided in at least one of the first pressure-contact portion and the second pressure-contact portion, and between the first sub-orifice groove and the inner peripheral surface of the outer cylinder. The first sub-orifice is formed, and a second sub-orifice groove extending in the circumferential direction is provided in at least one of the first pressure-contact portion and the second pressure-contact portion, and the second sub-orifice groove and the inner cylinder The second sub-orifice is formed between the peripheral surface and the first sub-orifice groove is provided with the rubber film-shaped first rubber valve, and the top of the first rubber valve is the inner peripheral surface of the outer cylinder. The first rubber valve is formed in an inclined posture in which the first rubber valve is positioned on the downstream side of the first sub-orifice toward the top, and the rubber film-like second rubber valve is formed in the second sub-orifice groove. So that the top of the second rubber valve is in pressure contact with the inner peripheral surface of the outer cylinder. Made is, the second rubber valve is formed in an inclined posture positioned on the downstream side of the second sub-orifice as the top side. In particular, the present invention includes not only the main orifice but also the first sub-orifice and the second sub-orifice on the outer peripheral surface of the connecting wall in this way, so that there is sufficient space for forming the main orifice on the outer peripheral surface. In the structure in which the main orifice cannot be ensured, the main orifice forming member can sufficiently secure the orifice length for the main orifice as described above.

  As described above, the liquid-filled vibration isolator of the present invention ensures a sufficient orifice length for the main orifice even in the liquid-filled vibration-proof device provided with the sub-orifice having a rubber valve. Can do. Further, it is possible to prevent liquid leakage in the vicinity of the main orifice and reliably exhibit a predetermined attenuation effect by the main orifice.

  Next, embodiments of the present invention will be described with reference to the drawings.

  1 to 6 show a liquid-filled vibration isolator 10 according to an embodiment of the present invention. As shown in FIG. 16, the liquid-filled vibration isolator 10 is a bush type vibration isolator that couples the lower link 1 of the suspension of the front wheel of the automobile and the vehicle body frame. In FIG. 16, reference numeral 2 represents a tire, and reference numeral 3 represents a ball joint.

  The vibration isolator 10 includes a cylindrical inner cylinder 12 connected to a vehicle body frame, and a cylindrical outer cylinder that coaxially surrounds the inner cylinder 12 and is press-fitted into the mounting hole 1A of the lower link 1. 14 and an anti-vibration base 16 made of a rubber-like elastic body interposed therebetween.

  Between the inner cylinder 12 and the outer cylinder 14, a first liquid chamber 18 and a second liquid chamber 20 having a vibration-proof base 16 as a chamber wall are formed so as to face both sides of the inner cylinder 12. Yes. The first liquid chamber 18 and the second liquid chamber 20 are communicated with each other via the main orifice 22. In addition, a first sub-orifice between the first liquid chamber 18 and the second liquid chamber 20 allows the liquid to flow only from the first liquid chamber 18 side to the second liquid chamber 20 side via the first rubber valve 24. 26 and a second sub-orifice 30 through which liquid flows only from the second liquid chamber 20 side to the first liquid chamber 18 side via the second rubber valve 28.

  Between the inner cylinder 12 and the outer cylinder 14, an intermediate cylinder 32 having a circular cross section that surrounds the inner cylinder 12 coaxially is disposed. The intermediate cylinder 32 is positioned on both sides of the inner cylinder 12 with the pair of ring-shaped fitting peripheral walls 34 and 36 on both ends in the axial direction on which the outer cylinder 14 is fitted, and more than the fitting peripheral walls 34 and 36. A pair of connecting walls 38 and 40 having an arcuate cross section are provided on the inner side in the radial direction and connecting the pair of fitting peripheral walls 34 and 36 to each other.

  As shown in FIGS. 2 and 5, the anti-vibration base 16 is provided between the inner side surface 38 </ b> A of the first connection wall 38, which is one of the connection walls, and the outer peripheral surface 12 </ b> A of the inner cylinder 12 facing this, and A pair of anti-vibration base bodies 16 are vulcanized and formed between the inner side surface 40A of the second connecting wall 40, which is a connecting wall, and the outer peripheral surface 12A of the inner cylinder 12 opposite to the inner side surface 40A. , 16 divides the first liquid chamber 18 and the second liquid chamber 20 in the circumferential direction.

  As shown in FIGS. 1 and 6, between the first fitting peripheral wall 34 that is one fitting peripheral wall and the inner cylinder 12 and between the second fitting peripheral wall 36 and the inner cylinder 12 that are the other fitting peripheral walls. The end walls 42, 42 made of a rubber-like elastic body are provided between them, and the pair of end walls 42, 42 are chamber walls at both axial ends of the first liquid chamber 18 and the second liquid chamber 20. Is forming. As shown in FIG. 6, the end wall 42 is formed in an inwardly curved shape, and more specifically, a cross-sectional curved shape in which a central portion 42 </ b> A in the height direction projects most toward the center in the axial direction. Is formed. As a result, when a load is input in a direction perpendicular to the axis P (a direction perpendicular to the axis O), the end wall 42 is bent inwardly in the compression-side liquid chamber, thereby deforming the compression-side liquid chamber. The volume change is increased to enhance the liquid flow action at the main orifice 22.

  As shown in FIG. 2, on the outer surface 38B side of the first connection wall 38, a first pressure contact portion 44 that is in pressure contact with the inner peripheral surface 14A of the outer cylinder 14 is formed of a rubber-like elastic body, and the second connection wall On the outer surface 40B side of 40, a second press-contact portion 46 that press-contacts the inner peripheral surface 14A of the outer cylinder 14 is provided by a rubber-like elastic body.

  As shown in FIGS. 7 and 8, the first press contact portion 44 is provided with a first fitting recess 48 extending in the circumferential direction at the central portion in the axial direction, and a pair of first extending in the circumferential direction on both sides in the axial direction. Sub-orifice grooves 50, 50 are formed. The first fitting recess 48 and the first sub-orifice groove 50 have a U-shaped cross section that opens outward in the radial direction, and are formed over the entire circumferential direction of the first connecting wall 38.

  The first sub-orifice 26 is formed by pressing the inner peripheral surface 14A of the outer cylinder 14 against the first sub-orifice groove 50. In this embodiment, the first sub-orifice 26 has two pieces in the first press-contact portion 44. First sub-orifices 26, 26 are provided in parallel to each other. The first rubber valves 24, 24 are respectively vulcanized and formed in the pair of first sub-orifice grooves 50, 50 so that the top 24A of the first rubber valve 24 is in pressure contact with the inner peripheral surface 14A of the outer cylinder 14. It is configured. In addition, the first rubber valve 24 is set to an inclined posture that is positioned on the downstream side of the first sub-orifice 26 toward the top 24A side (see FIGS. 5 and 15).

  As shown in FIG. 15, the first rubber valve 24 is formed in a rubber film shape, and a bulging portion 52 having an arcuate cross section that presses against the inner peripheral surface 14A of the outer cylinder 14 is formed over the entire width of the top portion 24A. Has been. The bulging portion 52 bulges from the membrane surface 24B on the side corresponding to the upstream side of the first sub-orifice 26 of the pair of membrane surfaces 24B, 24C of the first rubber valve 24 to the outer side R of the membrane surface 24B. ing. As shown in FIG. 8, the bulging portions 52 and 52 of the pair of first rubber valves 24 and 24 are located at the center in the circumferential direction of the first connecting wall 38. In addition, the bulging part 52 does not necessarily need to be the center of the circumferential direction of the 1st connection wall 38, and may shift | deviate from this center.

  As shown in FIG. 9, the second press-contact portion 46 is provided with a second fitting recess 54 extending in the circumferential direction at the central portion in the axial direction, and a pair of second sub-orifices extending in the circumferential direction on both sides in the axial direction. Grooves 56 and 56 are formed. The second fitting recess 54 and the second sub-orifice groove 56 have a U-shaped cross section that opens outward in the radial direction, and are formed over the entire circumferential direction of the second connecting wall 40. However, the 2nd fitting recessed part 54 is interrupted | blocked by the interruption | blocking part 58 in the center part of the circumferential direction, and is divided | segmented into the circumferential direction.

  The second sub-orifice 30 is formed by pressing the inner peripheral surface 14A of the outer cylinder 14 against the second sub-orifice groove 56. In this embodiment, the second sub-orifice 30 has two Second sub-orifices 30 are provided in parallel to each other. The second rubber valves 28, 28 are vulcanized and formed in the pair of second sub-orifice grooves 56, 56, respectively, so that the top portion 28A of the second rubber valve 28 is in pressure contact with the inner peripheral surface 14A of the outer cylinder 14. It is configured. In addition, the second rubber valve 28 is set to an inclined posture that is located on the downstream side of the second sub-orifice 30 toward the top portion 28A (see FIGS. 5 and 15).

  The second rubber valve 28 has the same shape and size as the first rubber valve 24. That is, as shown in FIG. 15, the second rubber valve 28 is formed in a rubber film shape, and includes the bulging portion 52 at the top portion 28 </ b> A. The bulging portion 52 is a pair of membrane surfaces of the second rubber valve 28. 28B and 28C bulge from the film surface 28B on the side corresponding to the upstream side of the second sub-orifice 30 to the outer side R of the film surface 28B. As shown in FIG. 9, the bulging portions 52 and 52 of the pair of second rubber valves 28 and 28 are located at the center in the circumferential direction of the second connecting wall 40. In addition, the bulging part 52 does not necessarily need to be the center of the circumferential direction of the 2nd connection wall 40, and may shift | deviate from this center.

  As shown in FIGS. 4 to 6, a first main orifice forming member 60 for forming the main orifice 22 is disposed in the first liquid chamber 18. As shown in FIGS. 10 and 13, the first main orifice forming member 60 has an arc shape, and a first main orifice groove 64 communicating with the first liquid chamber 18 through the first opening 62 on the outer peripheral surface thereof. Is provided. At both ends of the first main orifice forming member 60, a pair of fitting protrusions 66 and 68 are formed so as to protrude outward along the circumferential direction. The first main orifice groove 64 opens from the first opening 62 at the center in the circumferential direction of the first main orifice forming member 60 toward the outside in the circumferential direction at one fitting protrusion 66 so as to communicate with the outside. Is formed.

  An arc-shaped second main orifice forming member 70 similar to the first main orifice forming member 60 is also arranged in the second liquid chamber 20, and as shown in FIGS. A second main orifice groove 74 communicating with the second liquid chamber 20 via the second opening 72 is provided on the surface, and a pair of fittings formed to protrude outward along the circumferential direction at both ends. Protrusions 76 and 78 are provided. Similar to the first main orifice groove 64, the second main orifice groove 74 opens from the second opening 72 toward the outer side in the circumferential direction at one fitting protrusion 76.

  In the present embodiment, the first main orifice forming member 60 and the second main orifice forming member 70 are the same parts having the same shape and size, and thus by making the parts common, productivity and parts are improved. The cost is improved. Further, as the shape of the first main orifice groove 64 and the second main orifice groove 74, for example, in order to further extend the orifice length, the groove extending in the circumferential direction is folded once or a plurality of times and then fitted into one. The projections 66 and 76 can be provided so as to communicate with the outside.

  The first main orifice forming member 60 and the second main orifice forming member 70 are fitted to the respective fitting recesses 48 and 54 by fitting the pair of fitting protrusions 66 and 68; 76 and 78 to the respective liquid chambers. 18 and 20 are arranged in a state of being spanned between the first press contact portion 44 and the second press contact portion 46 on both sides.

  Specifically, as shown in FIGS. 8, 9, and 13, the one fitting projection 66 of the first main orifice forming member 60 is fitted into the first fitting recess 48 of the first pressure contact portion 44, The other fitting projection 68 is fitted into the second fitting recess 54 of the second pressure contact portion 46. Also, as shown in FIGS. 8, 9, and 12, the one fitting protrusion 76 of the second main orifice forming member 70 is fitted into the first fitting recess 48 of the first pressure contact portion 44, and the other The fitting protrusion 78 is fitted into the second fitting recess 54 of the second pressure contact portion 46.

  By assembling as described above, the outer peripheral surfaces of the first main orifice forming member 60 and the second main orifice forming member 70 are in pressure contact with the inner peripheral surface 14A of the outer cylinder 14, respectively. Further, in the first fitting recess 48 of the first pressure contact portion 44, the opening end 63 of the one fitting projection 66 of the first main orifice forming member 60 and the one fitting of the second main orifice forming member 70 are arranged. The opening end 73 of the mating protrusion 76 is abutted (see FIG. 8), and the first main orifice groove 64 and the second main orifice groove 74 are connected in communication. Thus, the main orifice 22 that communicates the first liquid chamber 18 and the second liquid chamber 20 is formed. The fitting recess 54 of the second press-contact portion 46 is not provided with a groove for forming an orifice in the fitting protrusions 68 and 78 inserted as described above, and the fitting recess 54 is a blocking portion. The first liquid chamber 18 and the second liquid chamber 20 are not communicated with each other in the fitting recess 54 because they are blocked at 58.

  As shown in FIGS. 4 and 6, inner stoppers 80 are provided in the first liquid chamber 18 and the second liquid chamber 20 so as to protrude radially outward from the inner cylinder 12 side. The inner stopper 80 is formed by covering a bulge portion provided over the entire circumference in the axially central portion of the inner cylinder 12 with a rubber film 82 integrally extending from the vibration-isolating base 16, and its tip The surface is formed into a convex curved surface. The inner stopper 80 may be formed in a protruding shape only on the first liquid chamber 18 and the second liquid chamber 20 side instead of the bulge shape of the entire circumference.

  In the first liquid chamber 18 and the second liquid chamber 20, outer stoppers 84 are provided on the radially outer side of the inner stopper 80, respectively. The outer stopper 84 is provided on each of the first main orifice forming member 60 and the second main orifice forming member 70, and radially inwardly facing the inner stopper 80 on the inner peripheral side of each member 60, 70. Protrusions are formed. The distal end surface of the outer stopper 84 facing the inner stopper 80 is formed in a concave curved surface having substantially the same curvature as that of the distal end surface of the inner stopper 80.

  As shown in FIGS. 7 to 9, a pair of rubber annular seal lips 86 and 88 extending in the circumferential direction are provided on the outer peripheral surfaces of the first and second fitting peripheral walls 34 and 36, respectively, at both ends in the axial direction. Is provided. Of these, the outer annular seal lip 86 is provided over the entire circumference in the circumferential direction. As shown in FIGS. 12 and 13, the inner annular seal lip 88 is provided over the entire circumference except for the notch portions 89 at only two locations facing the first liquid chamber 18. By providing the notch 89 in this way, the liquid that has entered between the two annular seal lips 86 and 88 when the liquid is sealed is inserted into the first liquid chamber 18 when the outer cylinder 14 is pressed into the press-fitting hole of the lower link. It can guide and can prevent the liquid leakage to the outside. Moreover, by opening only to the 1st liquid chamber 18 side, it can prevent that a liquid flows between both the liquid chambers 18 and 20 through the outer peripheral surface of the fitting surrounding walls 34 and 36. FIG.

  As shown in FIGS. 7 and 8, in the first pressure contact portion 44, one end in the width direction of the bulging portion 52 of the first rubber valve 24 provided in the first sub-orifice groove 50 adjacent to the first fitting peripheral wall 34. The first seal lip 90 made of rubber is connected to the side portion of the annular seal lip 88 on the inner side of the first fitting peripheral wall 34 and is vulcanized and formed on the outer peripheral surface 44 </ b> A of the first press-contact portion 44. Further, one end portion in the width direction of the bulging portion 52 of the first rubber valve 24 provided in the first sub-orifice groove 50 adjacent to the second fitting peripheral wall 36 and the inner annular shape of the second fitting peripheral wall 36. A rubber-made second seal lip 92 connected to the side of the seal lip 88 is vulcanized and formed on the outer peripheral surface 44 </ b> A of the first press-contact portion 44. The first seal lip 90, the bulging portion 52 of the pair of first rubber valves 24, and the second seal lip 92 are aligned in a straight line. As shown in FIG. 15, in the state before the first pressure contact portion 44 and the outer cylinder 14 are assembled, the bulging portion 52 of the first rubber valve 24 has an outer peripheral surface 44 </ b> A (the outer cylinder 14) of the first pressure contact portion 44. Projecting radially outward S from the pressure contact surface of the first pressure contact portion 44 with respect to the inner peripheral surface 14A. Similarly, the annular seal lip 88 and the first and second seal lips 90 and 92 protrude outward from the outer peripheral surface 44A.

  As shown in FIG. 9, in the second pressure contact portion 46, one end portion in the width direction of the bulging portion 52 of the second rubber valve 28 provided in the second sub-orifice groove 56 adjacent to the first fitting peripheral wall 34, A third seal lip 94 made of rubber that is continuous with the side portion of the inner annular seal lip 88 of the first fitting peripheral wall 34 is vulcanized and formed on the outer peripheral surface 46 </ b> A of the second press-contact portion 46. Further, one end portion in the width direction of the bulging portion 52 of the second rubber valve 28 provided in the second sub-orifice groove 56 adjacent to the second fitting peripheral wall 36, and the inner annular shape of the second fitting peripheral wall 36. A rubber-made fourth seal lip 96 connected to the side of the seal lip 88 is vulcanized on the outer peripheral surface 46 A of the second press-contact portion 46. Furthermore, a rubber-made fifth seal lip 98 is formed on the outer peripheral surface of the blocking portion 58 and is located between the bulging portions 52 of the pair of second rubber valves 28. The third seal lip 94, the bulging portion 52 of the pair of second rubber valves 28, the fourth seal lip 96, and the fifth seal lip 98 are aligned in a straight line. As shown in FIG. 15, the bulging portion 52 of the second rubber valve 28 is more radial than the outer peripheral surface 46 </ b> A of the second pressure contact portion 46 before the second pressure contact portion 46 and the outer cylinder 14 are assembled. It protrudes outward S. Similarly, the annular seal lip 88 and the third, fourth, and fifth seal lips 94, 96, and 98 protrude outward from the outer peripheral surface 46A.

  As shown in FIG. 14A, seal rubbers 100 and 100 are provided at both circumferential ends 38C and 38D of the first connecting wall 38, respectively. The seal rubber 100 is made of rubber continuous from the vibration isolation base 16, and is formed in a ridge that covers the end faces of the circumferential ends 38C and 38D and extends in the axial direction. More specifically, as shown in FIG. 7, the seal rubber 100 is provided in a central region including the first fitting recess 48 in the axial direction of the first connecting wall 38.

  14B, the seal rubber 100 on the first liquid chamber 18 side is fitted from the first liquid chamber 18 by pressing the circumferential end 60A of the first main orifice forming member 60 into pressure contact. Liquid leakage between the inner peripheral surface of the protrusion 66 and the outer peripheral surface of the first fitting recess 48 (the outer surface 38B of the first connecting wall 38) is prevented. Further, the seal rubber 100 on the second liquid chamber 20 side presses the circumferential end 70 </ b> A of the second main orifice forming member 70, so that the fitting protrusion 76 and the first fitting recess 48 from the second liquid chamber 20. Prevents liquid leakage between the two. At that time, a gap 102 is provided between the circumferential end 38C of the first connecting wall 38 and the circumferential end 60A of the first main orifice forming member 60 disposed to face the first connecting wall 38. A gap 102 is also provided between the circumferential end 38 </ b> D of the connecting wall 38 and the circumferential end 70 </ b> A of the second main orifice forming member 70 disposed to face the connecting wall 38. The seal rubber 100 is held in a compressed state and exhibits sealing performance.

  The gap 102 is set so as to be held even when the outer cylinder 14 is press-fitted into the mounting hole 1A of the lower link 1 which is a member to be mounted. In detail, the vibration isolator 10 of this embodiment is manufactured as follows. That is, a rubber molded body composed of the inner cylinder 12, the vibration isolation base 16 and the intermediate cylinder 32 is vulcanized and molded, and the resulting rubber molded body is fitted with the fitting peripheral walls 34 and 36 and the connecting walls 38 and 40 of the intermediate cylinder 32. By pressing the fitting recesses 48 and 54 and reducing the diameter of the intermediate cylinder 32, pre-compression is applied to the vibration-proof base 16. Next, as shown in FIG. 10, the main orifice forming members 60 and 70 are mounted, the outer cylinder 14 is covered with the liquid, the outer cylinder 14 is reduced in diameter, and both ends thereof are curled so that the vibration isolator 10 is can get. The outer cylinder 14 is further reduced in diameter by press-fitting the vibration isolator 10 into the mounting hole 1 </ b> A of the lower link 1. Thus, even when the diameter is reduced by press-fitting into the mounting hole 1A, the circumferential ends 38C, 38D of the first connecting wall and the circumferential ends 60A, 70A of the main orifice forming member are held in a non-contact manner. The gap 102 is ensured. In order to configure in this way, the width of the first connecting wall 38 and the dimensions of the main orifice forming member may be set in consideration of the inner diameter of the mounting hole 1A, the thickness of the outer cylinder 14, and the like.

  In addition, the structure sealed with such seal rubber 100 is employable similarly to the above also in the circumferential direction both ends 40C and 40D of the 2nd connection wall 40 (refer FIG. 4).

  As shown in FIG. 16, the vibration isolator 10 of the present embodiment having the above configuration has the outer cylinder 14 in the lower link 1 with the axial direction (axial center O) of the inner cylinder 12 facing the vehicle vertical direction. The inner cylinder 12 is connected to the vehicle body frame by being press-fitted into the mounting hole 1A at the rear end. In this case, when the tire 2 is displaced in the front-rear direction T, a load in the direction perpendicular to the axis P in the left-right direction of the vehicle is input to the vibration isolator 10 and becomes the main load input direction. Therefore, the vibration isolator 10 is mounted so that the first liquid chamber 18 and the second liquid chamber 20 face each other in this direction P. On the other hand, when the tire 2 is displaced in the vertical direction, a force that tries to rotate around the line L passing through the connecting portion at the front and rear of the lower link 1 acts, so the vibration isolator 10 has an axis O of the inner cylinder 12. In contrast, a load in the twisting direction Q that causes the axis of the outer cylinder 14 to tilt is input (see FIG. 6).

  In the vibration isolator 10, when the hydraulic pressure difference between the first liquid chamber 18 and the second liquid chamber 20 is less than a set value, the first rubber valve 24 and the second rubber valve 28 are kept closed, and the interior of the main orifice 22 is maintained. The liquid flows and the vibration is absorbed by the flowing action. When the fluid pressure difference between the fluid chambers 18 and 20 becomes a set value, the fluid pressure on the first fluid chamber 18 side is high, and the fluid pressure on the second fluid chamber 20 side is low, the first rubber valve 24 is elastically deformed by the fluid pressure. Then, the liquid passes between the bulging portion 52 of the first rubber valve 24 and the inner peripheral surface 14 </ b> A of the outer cylinder 14, and the liquid flows from the first liquid chamber 18 to the second liquid chamber 20. As a result, the fluid pressure in the first fluid chamber 18 is lowered, so that the end wall 42 that is curved inwardly can be prevented from warping outward, and its durability can be prevented from decreasing. When the fluid pressure on the second fluid chamber 20 side is high and the fluid pressure on the first fluid chamber 18 side is low, the second rubber valve 28 is elastically deformed and opened by the fluid pressure, and the second rubber valve 28 bulges. The liquid passes between the portion 52 and the inner peripheral surface 14 </ b> A of the outer cylinder 14, and the liquid flows from the second liquid chamber 20 to the first liquid chamber 18. As a result, the hydraulic pressure in the second liquid chamber 20 is lowered, and similarly, the durability of the end wall 42 forming the second liquid chamber 20 is prevented from being lowered.

  Further, in the vibration isolator 10, the first main orifice forming member 60 and the second main orifice forming member 70 provided in the first liquid chamber 18 and the second liquid chamber 20 are used for the main orifice 22. A sufficient length of the orifice can be ensured, and the resulting fluid flow action can be exhibited effectively.

  Further, since the seal rubber 100 is provided at the circumferential ends 38C and 38D of the first connecting wall 38 on the side where the main orifice 22 is formed, the seal rubber 100 is compressed and sealed by the main orifice forming members 60 and 70. In addition, liquid leakage from the first liquid chamber 18 and the second liquid chamber 20 to the fitting protrusions 66 and 76 and the first fitting recess 48 is prevented, and a predetermined damping effect by the main orifice 22 is reliably exhibited. be able to. In particular, in the above embodiment, the circumferential ends 38C and 38D of the first connecting wall and the circumferential ends 60A and 70A of the main orifice forming member are held in a non-contact manner even during press-fitting into the mounting hole 1A. Since the gap 102 in which the seal rubber 100 is interposed between the two is secured, the seal rubber 100 can be prevented from being broken at the time of press-fitting, and the liquid leakage can be prevented more reliably.

  Further, stoppers for limiting the relative displacement of the inner and outer cylinders 12 and 14 within a predetermined range are an inner stopper 80 from the inner cylinder 12 side and an outer stopper 84 from the first and second main orifice forming members 60 and 70. By dividing, it is possible to prevent the end wall 42 from being damaged at the time of displacement in the twisting direction Q. In particular, in this embodiment, although the end wall 42 is curved inward, contact between the end wall 42 and the stopper during displacement in the twisting direction Q can be effectively avoided. For such an operational effect, it is preferable to set the height (diameter dimension) of the outer stopper 84 to be equal to or greater than the height of the inner stopper 80.

  Furthermore, a bulging portion 52 that presses against the inner peripheral surface 14A of the outer cylinder 14 is formed on the top of the first rubber valve 24 and the second rubber valve 28 so as to bulge outward R. When the hydraulic pressure difference between the first and second fluid chambers 20 reaches a set value, the swollen portion 52 urges the swinging of the first rubber valve 24 or the second rubber valve 28 toward the opening side, and the opening speed thereof is increased. It becomes faster, and the time for lowering the hydraulic pressure difference between both liquid chambers to a desired value can be shortened.

  Further, when the first rubber valve 24 is kept in the closed state, the width of the first rubber valve 24 outwards between the outer peripheral surface 44A of the first pressure contact portion 44 and the inner peripheral surface 14A of the outer cylinder 14. The annular seal lip 88 and the first and second seal lips 90, 92 can prevent the liquid from flowing in the direction along the first sub-orifice 26. It is possible to avoid the problem that the first sub-orifice groove 50 is in a communicating state. Similarly, when the second rubber valve 28 is kept in the closed state, the second rubber valve 28 is located outside the second rubber valve 28 in the width direction between the outer peripheral surface 46A of the second press-contact portion 46 and the inner peripheral surface 14A of the outer cylinder 14. On the other side, the annular rubber seal lip 88 and the third, fourth and fifth seal lips 94, 96, 98 can prevent the liquid from flowing in the direction along the second sub-orifice 30, and the second rubber. A problem that the second sub-orifice groove 56 portions on both sides of the valve 28 are in communication can be avoided.

  Further, when the rubber valves 24 and 28 are molded by a molding die (not shown), a first mold disposed on one film surface side and a second mold disposed on the other film surface side are respectively provided. Although the mold is pulled out to the outside of the membrane surface, the bulging portion 52 of both the rubber valves 24 and 28 is formed on the side of the membrane surface corresponding to the upstream side of the sub-orifices 26 and 30 as described above. Since it bulges outward 24R from 24B, 28B, a part of the 1st type and the 2nd type is not caught on the bulging part 52 at the time of demolding, and demolding can be performed smoothly. Further, in the state before the outer cylinder 14 is assembled, the bulging portions 52 of both the rubber valves 24 and 28 are radially outward from the pressure contact surfaces of the pressure contact portions 44 and 46 with respect to the inner peripheral surface 14A of the outer cylinder 14. Therefore, the pressure contact force of the bulging portion 52 against the inner peripheral surface 14A of the outer cylinder 14 can be increased. Therefore, liquid leakage from between the bulging portion 52 and the inner peripheral surface 14A of the outer cylinder 14 when the hydraulic pressure difference is less than the set value can be prevented more reliably.

  In the above embodiment, the first pressure contact portion 44 is provided with two first sub-orifice grooves 50, 50, and the second pressure contact portion 46 is provided with two second sub-orifice grooves 56, 56. The second sub-orifice groove 56 may be provided in the first pressure contact portion 44, and the first sub-orifice groove 50 may be provided in the second pressure contact portion 46. Also, the first pressure contact portion 44 may be provided with the first and second sub-orifice grooves 50 and 56, and the second pressure contact portion 46 may be provided with the first and second sub-orifice grooves 50 and 56. In addition, only one of the first sub-orifice groove 50 and the second sub-orifice groove 56 can be provided in each pressure contact portion 44, 46.

The side view of the liquid enclosure type vibration isolator which concerns on one Embodiment of this invention. II-II sectional view taken on the line of FIG. The front view of the vibration isolator. IV-IV sectional view taken on the line of FIG. VV sectional view taken on the line of FIG. FIG. 6 is a sectional view taken along line VI-VI in FIG. 3. The front view which shows the state before attaching a main orifice formation member to the rubber molding containing the inner cylinder and intermediate | middle cylinder of the vibration isolator. The front view which shows the state after the assembly | attachment of FIG. The figure which looked at the state of FIG. 8 from back. The side view which shows the state before attaching a main orifice formation member to this rubber molding. The front view which shows the state before attaching a main orifice formation member to this rubber molding. The front view which shows the state after the assembly | attachment of FIG. The figure which looked at the state of FIG. 12 from back. (A) is a principal part expanded sectional view which shows the state before assembling a main orifice formation member to the said rubber molded object, (b) is a figure which shows the state after the assembly | attachment. The figure which shows a rubber valve. Schematic which shows the mounting state to the vehicle of the said vibration isolator.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Lower link (member to be attached), 1A ... Mounting hole, 10 ... Liquid filled vibration isolator, 12 ... Inner cylinder, 12A ... Outer surface of inner cylinder, 14 ... Outer cylinder, 14A ... Inner circumference of outer cylinder 16, vibration isolating substrate, 18, first liquid chamber, 20, second liquid chamber, 22, main orifice, 24, first rubber valve, 24 A, top of the first rubber valve, 26, first suborifice, 28 ... second rubber valve, 28A ... top of the second rubber valve, 30 ... second suborifice, 32 ... intermediate cylinder, 34 ... first fitting peripheral wall, 36 ... second fitting peripheral wall, 38 ... first connecting wall 38A, the inner surface of the first connecting wall, 38B, the outer surface of the first connecting wall, 38C, 38D, the circumferential end of the first connecting wall, 40, the second connecting wall, 40A, the inner surface of the second connecting wall, 40B ... the outer surface of the second connecting wall, 42 ... the end wall, 44 ... the first pressure contact portion, 44A ... the outer peripheral surface of the first pressure contact portion, 46 ... the second pressure contact portion, 46A ... the first. The outer peripheral surface of the pressure contact portion, 48 ... first fitting recess, 50 ... first sub-orifice groove, 54 ... second fitting recess, 56 ... second sub-orifice groove, 60 ... first main orifice forming member, 60A ... periphery Direction end 62: First opening 64 ... First main orifice groove 66, 68 ... Fitting projection of first main orifice forming member 70 ... Second main orifice forming member 70A ... Circumferential end 72, second opening, 74, second main orifice groove, 76, 78, fitting protrusion of the second main orifice forming member, 80, inner stopper, 84, outer stopper, 100, sealing rubber, 102, gap

Claims (5)

An inner cylinder (12), an outer cylinder (14) surrounding the inner cylinder in an axially parallel manner, a vibration-proof base (16) made of a rubber-like elastic body interposed between the inner cylinder and the outer cylinder, and the inner cylinder An intermediate cylinder (32) positioned between the first cylinder and the outer cylinder, a first liquid chamber (18) and a second liquid chamber (20) positioned across the inner cylinder, the first liquid chamber and the second liquid chamber An anti-vibration device comprising a main orifice (22) for communicating
The intermediate cylinder (32) is positioned between a pair of ring-shaped fitting peripheral walls (34, 36) on both end sides in the axial direction to which the outer cylinder is fitted, and the inner cylinder between the fitting peripheral walls. A pair of connecting walls (38, 40) that are located on the radially inner side and connect the pair of fitting peripheral walls.
The anti-vibration base (16) combines the inner surface (38A, 40A) of the pair of connecting walls and the outer peripheral surface (12A) of the inner cylinder facing the inner surface, and the first liquid chamber The second liquid chamber is partitioned in the circumferential direction, and end walls (42, 42) made of a rubber-like elastic body are provided between the pair of fitting peripheral walls and the inner cylinder, A wall forms a chamber wall at an axial end of the first liquid chamber and the second liquid chamber;
A first pressure contact portion (44) made of a rubber-like elastic body that is in pressure contact with the inner peripheral surface of the outer cylinder is provided on the outer surface (38B) side of one of the connecting walls, and a first fitting is performed on the first pressure contact portion. A recess (48) is provided, and a second press-contact portion (46) made of a rubber-like elastic body that presses against the inner peripheral surface of the outer cylinder is provided on the outer surface (40B) side of the other connecting wall. A second fitting recess (54) is provided in the two pressure contact parts,
A first main orifice forming member (60) having a first main orifice groove (64) communicating with the first liquid chamber through a first opening (62) in the outer periphery of the first liquid chamber (18). And fitting protrusions (66, 68) projecting from both circumferential ends of the first main orifice forming member, and the first main orifice groove is formed in one of the fitting protrusions (66). Open to the outside in the circumferential direction,
The first main orifice forming member has the one fitting projection (66) as the first fitting recess (48) and the other fitting projection (68) as the second fitting recess (54). ) Are respectively fitted to each other in the first liquid chamber (18) so as to be spanned between the first press contact portion (44) and the second press contact portion (46) on both sides, The outer peripheral surface of the first main orifice forming member (60) is in pressure contact with the inner peripheral surface of the outer cylinder (14), and the first main orifice groove (64) is in the second press contact portion (44). The main orifice (22) is formed by communicating with the liquid chamber (20) side,
A seal rubber (100) is provided at a circumferential end (38C) on the first liquid chamber side of the one connecting wall (38) provided with the first fitting recess, and the first main orifice is provided to the seal rubber. By pressing the circumferential end (60A) of the forming member (60) between the one fitting projection (66) and the first fitting recess (48) from the first liquid chamber (18). A liquid-sealed vibration isolator characterized by preventing liquid leakage to the water.   A gap (102) is provided between the circumferential end (38C) of the one connecting wall and the circumferential end (60A) of the first main orifice forming member, and the seal rubber (100) is provided in the gap. Is compressed and held, and the gap (102) is held in a state where the outer cylinder (14) is press-fitted into the mounting hole (1A) of the mounted member (1). The liquid-filled vibration isolator according to claim 1.   An inner stopper (80) protruding radially outward from the inner cylinder (12) side is provided in the first liquid chamber (18), and the first main orifice forming member (60) The liquid-filled vibration isolator according to claim 1 or 2, further comprising an outer stopper (84) that protrudes inward in the radial direction so as to face the inner stopper. A second main orifice forming member (70) having a second main orifice groove (74) communicating with the second liquid chamber through a second opening (72) in the outer peripheral surface in the second liquid chamber (20). Are provided, and fitting protrusions (76, 78) are provided at both ends in the circumferential direction of the second main orifice forming member, and the second main orifice groove is formed around one of the fitting protrusions (76). Opening toward the outside of the direction,
The second main orifice forming member has the one fitting projection (76) as the first fitting recess (48) and the other fitting projection (78) as the second fitting recess (54). ) Are respectively fitted to each other in the second liquid chamber (20) so as to be spanned between the first press contact part (44) and the second press contact part (46) on both sides, The outer peripheral surface of the second main orifice forming member (70) is brought into pressure contact with the inner peripheral surface of the outer cylinder (14), and the first main orifice groove (64) and the second main surface in the first press contact portion (44). The main orifice (22) is formed by communicating with the main orifice groove (74),
A seal rubber (100) is provided at a circumferential end (38D) on the second liquid chamber side of the one connecting wall (38) provided with the first fitting recess, and the second main orifice is provided to the seal rubber. By pressing the circumferential end (70A) of the forming member (70) between the one fitting projection (76) and the first fitting recess (48) from the second liquid chamber (20). The liquid-filled type vibration damping device according to claim 1, wherein liquid leakage to the liquid is prevented. A first sub-orifice (26) through which liquid flows only from the first liquid chamber side to the second liquid chamber side via the first rubber valve (24), and the second via the second rubber valve (28). A second sub-orifice (30) for allowing the liquid to flow only from the liquid chamber side to the first liquid chamber side,
A first sub-orifice groove (50) extending in the circumferential direction is provided in at least one of the first pressure-contact portion and the second pressure-contact portion, and between the first sub-orifice groove and the inner peripheral surface of the outer cylinder. The first sub-orifice (26) is formed;
A second sub-orifice groove (56) extending in the circumferential direction is provided in at least one of the first press-contact portion and the second press-contact portion, and between the second sub-orifice groove and the inner peripheral surface of the outer cylinder. The second sub-orifice (30) is formed;
The first sub-orifice groove (50) is provided with the rubber film-shaped first rubber valve (24) so that the top (24A) of the first rubber valve is in pressure contact with the inner peripheral surface of the outer cylinder. Configured, the first rubber valve is formed in an inclined posture located on the downstream side of the first sub-orifice (26) toward the top side,
The second sub-orifice groove (56) is provided with the rubber film-like second rubber valve (28) so that the top (28A) of the second rubber valve is in pressure contact with the inner peripheral surface of the outer cylinder. 5. The liquid sealing according to claim 1, wherein the second rubber valve is formed in an inclined posture in which the second rubber valve is positioned downstream of the second sub-orifice (30) toward the top side. Type vibration isolator.

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