JP2012087894A - Liquid-charged vibration control device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress abnormal sound produced due to repetition of the separation and abutment of a separate stopper rubber and a bracket and rubbing between them in a liquid-charged vibration control device containing a bracket.SOLUTION: A liquid-charged vibration control device 1 is provided with a main spring part 5 and an engine bracket 3 having substantially cylindrical casing part 3a. A pair of stopper rubbers 11 are mounted in the casing part 3a from a lateral direction, are provided with a stopper body part 51 held in an outer side surface of the casing part 3a and an upper and lower side stopper mounting parts 61, 71, and are mounted so as to vertically sandwich the casing part 3a. The stopper mounting parts 61, 71 are provided with an upper and lower side projected parts 61a, 71a fitted in recessed grooves 3d, 3e formed in both upper and lower end surfaces of the casing 3a. An inner projected part 51c is provided to an inner surface of the stopper body part 51 so as to form an inner groove 51d.

Description

  The present invention relates to a liquid-filled vibration isolator that encloses a fluid, for example, used in a mount of an automobile engine or the like.

  Conventionally, as this type of liquid-filled vibration isolator, a rubber elastic body is interposed between the mounting bracket on the engine side and the support bracket on the vehicle body side, and the volume changes as the rubber elastic body deforms. In many cases, a liquid chamber is formed between the two members, the liquid chamber is divided into a pressure receiving chamber and an equilibrium chamber, and an orifice passage is provided to communicate the pressure receiving chamber and the equilibrium chamber. In such a liquid filled type vibration isolator, the liquid flows between the pressure receiving chamber and the equilibrium chamber via the orifice passage, so that the vibration from the engine is absorbed and damped.

  In addition, in this type of liquid-filled vibration isolator, a stopper rubber formed integrally with the rubber elastic body is provided so as to cover a part of the outer peripheral surface of the support metal fitting, and for example, a large drive such as during sudden acceleration of an automobile is provided. In many cases, when the reaction force acts and the engine or the like tends to shake, the stopper rubber comes into contact with a member on the vehicle body side to limit the deformation of the rubber elastic body in the front-rear direction.

  Further, in such a liquid-filled vibration isolator, the bracket is used as the support metal fitting itself, in other words, the casing of the bracket in which the substantially cylindrical casing portion having the through hole and the mounting portion are integrally formed. A part in which a rubber elastic body is molded at the same time is known. For example, in Patent Document 1, a substantially cylindrical second mounting bracket (corresponding to a bracket) formed so that a mounting portion through which a plurality of fixing holes are provided protrudes radially outward, A liquid-filled vibration isolator is disclosed in which a main rubber elastic body and a buffer rubber layer (corresponding to a stopper rubber) integrally formed with the main rubber elastic body are vulcanized and bonded.

JP 2006-90531 A

  However, in the case where the rubber elastic body and the stopper rubber are simultaneously molded on the bracket as in the above-mentioned Patent Document 1, there are the following problems. In other words, conventionally, since the bracket was small, it was possible to mold a plurality of integrally vulcanized molded products (in which a rubber elastic body and a stopper rubber were molded at the same time on the bracket) with a single mold. Today, with the improvement in engine performance, a large bracket is required, and the number of integrally vulcanized molded products that can be molded in one mold is limited. There is a problem that it is bulky.

  Therefore, in order to reduce the manufacturing cost of the liquid-filled vibration isolator, a plurality of molds can be formed in a single mold, for example, an integral vulcanized molded product in which a mounting bracket and a metal pipe member are connected by a rubber elastic body (main spring portion) ) Is press-fitted into a substantially cylindrical support fitting constituting the bracket, and a stopper rubber separate from the rubber elastic body is attached to the outer side surface of the support fitting.

  However, in such a structure, when vibration is input to the liquid-filled vibration isolator, the inner side surface of the stopper rubber and the outer side surface of the support metal are repeatedly separated and contacted or rubbed, resulting in abnormal noise. There is a problem that occurs.

  The present invention has been made in view of the above points, and an object of the present invention is to provide a stopper for a liquid-filled vibration isolator having a bracket even when a separate stopper rubber is attached to the outer side surface of the bracket. An object of the present invention is to provide a technique for suppressing abnormal noise generated by repeated separation and contact between the inner side surface of rubber and the outer side surface of the bracket or rubbing.

  In order to achieve the above object, in the present invention, by firmly attaching the stopper rubber to the bracket, even when vibration is input, the contact state between the two is maintained, and the inner side surface of the stopper rubber and the outer side surface of the bracket are The contact area is reduced to suppress the generation of abnormal noise due to rubbing.

  Specifically, according to the first aspect of the present invention, a main spring portion in which a mounting bracket attached to a vehicle body and a cylindrical body are connected by a rubber elastic body, a substantially cylindrical casing portion having a through hole, and the casing portion are connected to an engine. A bracket integrally formed with a mounting portion for mounting on the side, and by pressing the cylindrical body into the through hole, the rubber elastic body and the inner peripheral surface of the casing portion are connected to the wall portion. The present invention is intended for a liquid-filled vibration isolator in which a part of the liquid chamber having a variable volume is formed.

  And it is further provided with the rubber-made stopper part attached from the cylinder radial direction outer side with respect to the said casing part, The said stopper part is substantially rectangular shaped stopper main-body part hold | maintained at the outer side surface of the said casing part, and the said stopper A pair of upper and lower stopper mounting portions extending inward in the cylinder radial direction from both ends of the main body in the cylindrical axis direction, and the casing portion is formed into a cylindrical shaft by the pair of upper and lower stopper mounting portions. It is attached to the casing part so as to be sandwiched in the direction, and the stopper attaching part has convex parts protruding inward in the cylindrical axis direction, which are fitted into concave parts formed at both ends of the casing part in the cylindrical axis direction. Each of the stopper main body portions is formed with a protruding portion that protrudes inward in the cylindrical radial direction so as to form a groove portion. Than is.

  According to the first invention, since the main spring portion and the stopper portion are separated from the bracket, a plurality of main spring portions and stopper portions can be formed by one molding.

  Further, the stopper main body is held on the outer side surface of the casing portion by fitting the convex portions protruding from the stopper mounting portion into the concave portions formed on both end surfaces in the cylinder axis direction of the casing portion. And since the protrusion part which protrudes inside a cylinder radial direction is formed in the inner surface of this stopper main-body part, when the stopper part is attached to a casing part, the said protrusion part will be the outer side surface of a casing part. Press inward in the cylinder radial direction. As a result, the convex part protruding from the stopper mounting part and the protruding part projecting inward in the cylinder radial direction act as if sandwiching the casing part in the cylindrical radial direction, so the stopper part is securely attached to the casing part. It is done. Therefore, even when a separate stopper rubber is attached to the outer side surface of the bracket, it is possible to suppress noise generated by the separation and contact between the inner side surface of the stopper rubber and the outer side surface of the bracket.

  Further, since the protrusion is formed so as to form a groove on the inner surface of the stopper main body, the presence of the groove causes the contact area between the inner surface of the stopper main body and the outer side of the casing portion. Will be reduced. Thereby, even when the inner side surface of the stopper rubber and the outer side surface of the bracket are rubbed, generation of abnormal noise can be suppressed.

  According to a second aspect of the present invention, in the first aspect of the present invention, the outer surface of the stopper main body is formed with a protruding portion that protrudes outward in the cylinder radial direction so as to form a groove portion. A substantially rectangular main body corresponding to the stopper main body, and a pair of upper and lower extending portions extending inward in the cylinder radial direction from both ends of the main body in the cylinder axis direction are formed in a substantially U-shaped cross section. A reinforcing member is embedded, and an opening is formed in the main body of the reinforcing member.

  According to the second aspect of the present invention, since the substantially U-shaped reinforcing member is embedded in the stopper portion having a substantially U-shaped cross section, the durability of the stopper portion is improved. Can do.

  In addition, since an opening is formed in the main body portion of the reinforcing member embedded in the stopper main body portion, the stopper main body portion is located on the inner side in the cylinder radial direction by the reinforcing member at a portion corresponding to the opening portion in the stopper main body portion. Since it is not divided to the outside, a suitable rubber volume is secured. And since the groove part is formed in both the outer side surface and inner side surface of the stopper main-body part, these groove parts are easily deformed by being crushed. Thus, since the stopper main body portion has an appropriate rubber volume and is formed in a shape that is easily deformed, it exhibits a soft spring characteristic.

  Then, when the deformation of the stopper main body progresses and the groove is crushed, the portion corresponding to the opening in the stopper main body tries to deform so as to escape in the cylinder axial direction and the cylinder circumferential direction, but the opening is partitioned. Such deformation is suppressed by the frame-shaped reinforcing member main body. Thereby, a stopper main-body part exhibits a hard spring characteristic.

  As described above, a highly durable stopper rubber having a two-stage characteristic that has a region that is greatly deformed and absorbs an impact when a load is input and a region that is not significantly deformed and suppresses displacement even when a load is input. It can be realized.

  According to the liquid-filled vibration isolator according to the present invention, the main spring portion, the stopper portion, and the bracket are separated from each other, so that a plurality of main spring portions and stopper portions can be formed by one molding. .

  The inner surface of the stopper main body held on the outer side surface of the casing portion by fitting the convex portions protruding from the stopper mounting portion into the concave portions formed on both end surfaces in the cylindrical axis direction of the casing portion. Is formed with a protruding portion that protrudes inward in the cylindrical radial direction, so that when the stopper portion is attached to the casing portion, a protruding portion that protrudes from the stopper mounting portion and a protruding portion that protrudes inward in the cylindrical radial direction Since it acts as if the casing portion is sandwiched in the cylinder radial direction, the stopper portion is firmly attached to the casing portion. Therefore, even when a separate stopper rubber is attached to the outer side surface of the bracket, it is possible to suppress noise generated by the separation and contact between the inner side surface of the stopper rubber and the outer side surface of the bracket.

  Further, since the protrusion is formed so as to form a groove on the inner surface of the stopper main body, the presence of the groove causes the contact area between the inner surface of the stopper main body and the outer side of the casing portion. Therefore, even when the inner side surface of the stopper rubber and the outer side surface of the bracket are rubbed, the generation of abnormal noise can be suppressed.

It is a perspective view which shows the liquid enclosure type vibration isolator which concerns on embodiment of this invention. It is the II-II sectional view taken on the line of FIG. It is sectional drawing explaining typically the state which press-fits a main spring part to the through-hole of a bracket. It is a perspective view which shows the state which fixed the liquid enclosure type vibration isolator to the attachment bracket. It is sectional drawing explaining the deformation | transformation behavior of a cylinder. It is a figure which shows the hole wall of a through-hole typically. It is sectional drawing which shows typically the cylinder deform | transformed by press-fitting in a through-hole. It is sectional drawing which shows a seal | sticker part, The same figure (a) shows the state before press injection, and the same figure (b) shows the press-fitted state. It is a perspective view which shows a stopper rubber. It is a figure which shows stopper rubber, The figure (a) is the sectional view on the AA line of the figure (c), The figure (b) is a front view which shows an outer surface, The figure (c) ) Is a longitudinal sectional view, FIG. 6D is a rear view showing the inner surface, and FIG. 8E is a sectional view taken along line EE in FIG. It is a perspective view which shows a reinforcement member. It is a figure explaining the mode of a deformation | transformation of a stopper rubber, The figure (a) shows the conventional thing which simultaneously molded the stopper rubber in the bracket, The figure (b) shows the thing of this embodiment. It is a graph which shows the load-deflection curve of stopper rubber.

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

-Overall structure-
1 and 2 are diagrams showing a liquid-filled vibration isolator according to the present embodiment. As shown in FIGS. 1 and 2, this liquid-filled vibration isolator 1 is an engine having a through hole 13 that is attached to a power plant (engine side) (not shown) formed by combining an engine and a transmission. A bracket 3, a main spring portion 5 press-fitted into the through-hole 13 from the lower side (one side in the cylinder axis direction), an orifice plate 7 inserted into the through-hole 13 from the upper side (the other side in the cylinder axis direction), A diaphragm 9 press-fitted into the through-hole 13 from the upper side so as to overlap the orifice plate 7; a pair of stopper rubbers (stopper portions) 11 attached to the engine bracket 3 from the side (outside in the cylinder radial direction); It has.

  The main spring portion 5 includes an aluminum alloy inner plate (mounting bracket) 25 connected to the vehicle body side, an aluminum alloy outer pipe (tubular body) 15, and rubber vulcanized and bonded to connect them. As shown in FIG. 3, the outer pipe 15 is press-fitted into the through hole 13 and attached to the engine bracket 3. Thus, the liquid-filled vibration isolator 1 of the present embodiment has a power so that the cylinder axis direction of the outer pipe 15 faces the vertical direction and the pair of stopper rubbers 11 face each other in the vehicle front-rear direction. It can be attached to the plant and the car body.

  In this liquid-filled vibration isolator 1, a buffer solution such as ethylene glycol is contained in a cavity defined by the inner peripheral surface of the engine bracket 3, the main spring portion 5 (specifically, the rubber elastic body 35), and the diaphragm 9. The cavity forms a liquid chamber 31 for absorbing and mitigating vibrations of the power plant input to the rubber elastic body 35. Thus, the interior of the liquid chamber 31 is divided up and down by the orifice plate 7, and the lower side thereof is a pressure receiving chamber 31 a whose volume is enlarged or reduced as the rubber elastic body 35 is deformed. The upper side of the chamber 31 is an equilibrium chamber 31b that absorbs fluctuations in the volume in the pressure receiving chamber 31a by expanding or reducing the volume by deformation of the diaphragm 9.

  As shown in FIG. 4, the liquid-filled vibration isolator 1 has a substantially inverted U-shape that is attached to a vehicle body side frame (not shown) so as to straddle the liquid-filled vibration-proof device 1 in the front-rear direction. The power plant is elastically supported by being attached to the vehicle body via the mounting bracket 21. The mounting bracket 21 includes an upper beam portion 21a extending substantially horizontally in the front-rear direction above the liquid-filled vibration isolator 1, and a pair of front and rear leg portions 21b extending downward from both front and rear ends of the upper beam portion 21a. The lower part 21c extends substantially horizontally in the front-rear direction below the liquid-filled vibration isolator 1 so as to connect the leg parts 21b. The lower ends 21d are fastened on the side frames. Thus, the liquid filled type vibration isolator 1 is attached to the mounting bracket 21 by fixing the inner plate 25 of the main spring portion 5 to the lower beam portion 21c.

  As a result, in the liquid filled type vibration damping device 1, for example, when the automobile is stopped and the engine is in an idle operation state, low-frequency idle vibration caused by torque fluctuation or the like is absorbed by the rubber elastic body 35, and the vehicle body Vibration transmission to is suppressed. On the other hand, when a large driving reaction force (torque) acts, for example, during a sudden acceleration of an automobile, the power plant tends to swing back and forth, a pair of stopper rubbers 11 (more specifically, outer ridges 51a described later) By contacting the leg portion 21b of the mounting bracket 21, the front and rear deformation of the rubber elastic body 35 is restricted, and when the power plant tries to swing up and down, a pair of stopper rubbers 11 (protrusions described later in more detail). The upper and lower deformations of the rubber elastic body 35 are restricted by the portion 61b) coming into contact with the upper beam portion 21a of the mounting bracket 21.

-Engine bracket, etc.-
The engine bracket 3 is made of an aluminum alloy, and the engine bracket 3 is formed with a through-hole 13 extending in the vertical direction for inserting the main spring portion 5 and the like as described above. In other words, the engine bracket 3 has such a shape that an attachment portion 3b for attaching the casing portion 3a to the power plant is integrally formed with the substantially cylindrical casing portion 3a having the through hole 13. The casing portion 3a is formed with a pair of mounting pedestal portions 3c each projecting in the cylinder radial direction from the outer peripheral surface and having a flat outer surface. The pair of mounting base portions 3c are for mounting the pair of stopper rubbers 11, and are formed so as to face each other in the front-rear direction. Further, on the upper surface and the lower surface of each mounting base portion 3c, concave groove portions 3d and 3e are formed, respectively, into which convex ridge portions 61a and 71a of a stopper rubber 11 described later are fitted.

  The through hole 13 of the casing part 3a is connected to the upper through hole 23 into which the orifice plate 7 and the diaphragm 9 are inserted, and the lower side into which the main spring part 5 is inserted. And a through hole 43. Thus, the inner diameter of the upper through hole 23 is formed larger than the inner diameter of the lower through hole 43.

  The stepped portion 33 is provided with a disc-shaped orifice plate 7 from above, and further, a substantially hat-shaped rubber diaphragm 9 is provided so as to cover the entire orifice plate 7 from above. . A substantially cylindrical reinforcing plate 19 is embedded on the outer peripheral side of the diaphragm 9, and the diaphragm 9 is inserted into the engine bracket 3 by being press-fitted into the upper through hole 23 from above. It is fixed in the fitted state. Further, in the state in which the diaphragm 9 is fitted and fixed in this manner, the outer periphery of the orifice plate 7 is surrounded by the upper seal rubber portion 9 a extending downward from the reinforcing plate 19.

  An annular orifice passage (not shown) is formed in the orifice plate 7 so as to extend in the circumferential direction, and one end of the orifice passage opens toward the pressure receiving chamber 31a below the liquid chamber 31, The other end of the orifice passage opens toward the equilibrium chamber 31b above the liquid chamber 31. The buffer solutions in the pressure receiving chamber 31a and the equilibrium chamber 31b circulate through the orifice passage so that the low-frequency vibration acting on the pressure receiving chamber 31a from the rubber elastic body 35 is attenuated. .

−Main spring part−
The inner plate 25 of the main spring portion 5 has a substantially rectangular bottom plate portion 55b and a side plate portion 55a extending downward from one side edge in the longitudinal direction of the bottom plate portion 55b. Part 55 and a substantially top-like inner pipe part 45 in which the bottom plate part 55b of the mounting plate part 55 is bulged upward. The inner pipe portion 45 is arranged substantially coaxially with the outer pipe 15 so that the upper end portion thereof is positioned at the approximate center of the lower end opening portion of the outer pipe 15 of the main spring portion 5, and corresponds to the outer peripheral surface thereof. A rubber elastic body 35 is interposed between the inner peripheral surface of the outer pipe 15 to be performed. On the other hand, the mounting plate portion 55 bends the side beam portion on the other side in the longitudinal direction of the bottom plate portion 55b so as to sandwich the lower beam portion 21c of the mounting bracket 21 from the left and right together with the side plate portion 55a and caulk the lower surface thereof. Further, the lower beam portion 21c is attached from above.

  A mortar-shaped concave portion 35 a is formed on the lower inner peripheral side of the rubber elastic body 35, and the peripheral surface of the concave portion 35 a is bonded to the outer peripheral surface of the inner pipe portion 45. The rubber elastic body 35 has a substantially truncated cone shape extending radially outward from the entire circumference of the inner pipe portion 45 and extending obliquely upward. The outer peripheral surface of the upper portion of the rubber elastic body 35 is the outer pipe 15. Bonded to the inner peripheral surface. Thus, the upper part of the rubber elastic body 35 that is bonded and fixed to the inner periphery of the outer pipe 15 has a relatively thick cylindrical shape that opens upward, and its upper end 35b is the outer pipe 15's. The upper end portion 15e is covered. Then, by fitting the outer pipe 15 into the lower through-hole 43, the liquid filled type vibration isolator 1 has the rubber elastic body 35 and the inner peripheral surface of the lower through-hole 43 as a part of the wall portion. A variable volume liquid chamber 31 is formed.

  By the way, in the structure in which the metal outer pipe 15 is press-fitted into the through hole of the metal engine bracket 3, the metal surfaces are in direct contact with each other. There is a risk.

  Therefore, in the liquid-filled vibration isolator 1 of the present embodiment, the outer pipe 15 is not in a cylindrical shape with a constant diameter, but is on the inner plate 25 side in the cylinder axis direction in order to improve the sealing performance with the engine bracket 3. A lower large-diameter cylindrical portion 15c and an upper small-diameter cylindrical portion 15a having an outer diameter smaller than that of the large-diameter cylindrical portion 15c and connected to the large-diameter cylindrical portion 15c through a step portion 15b. It has a step structure. The reason why such a two-stage structure is adopted is as follows.

  That is, in the two-stage structure in which the small-diameter cylindrical portion 15a is connected to the large-diameter cylindrical portion 15c through the step portion 15b, as shown in FIG. The inner peripheral surface of the lower through-hole 43 of the lower side of the engine bracket 3 by utilizing the property that the step portion 15b having high rigidity in the cylinder radial direction becomes a fulcrum and the small diameter cylindrical portion 15a expands upward and outward in the cylindrical radial direction. This is to fill a gap between the outer peripheral surface of the outer pipe 15 and the outer pipe 15. In addition, the code | symbol 15d in a figure is a flange part formed by bend | folding the lower end part of the large diameter cylinder part 15c to a cylinder radial direction outer side.

  Then, the lower through-hole 43 of the engine bracket 3 is, as shown in FIG. 6, the lower large-diameter portion facing the large-diameter cylindrical portion 15 c so as to correspond to the two-stage outer pipe 15. 43c and an upper small-diameter portion 43a that is continuous with the large-diameter portion 43c through a stepped portion 43b and faces the small-diameter cylindrical portion 15a. The large-diameter portion 43c is formed so that its inner diameter is larger than the outer diameter of the small-diameter cylindrical portion 15a and smaller than the outer diameter of the large-diameter cylindrical portion 15c. It is formed larger than the outer diameter of the portion 15a.

  The large-diameter portion 43c is inclined 1.5 ° so as to incline toward the outside in the cylinder radial direction toward the lower side in order to ensure the draft of the mold when the engine bracket 3 is molded. As described above, since the large-diameter portion 43c is inclined, in the liquid-filled vibration isolator 1 of this embodiment, the large-diameter cylindrical portion 15c can be easily inserted into the large-diameter portion 43c, and the large-diameter portion 43c There is also an advantage that the portion 43c serves as a guide that promotes deformation of the large-diameter cylindrical portion 15c.

  In the present embodiment, the hole wall of the large-diameter portion 43c is inclined by 1.5 °. However, the present invention is not limited to this. For example, the hole wall may not be inclined by performing cutting in a subsequent process. In addition, the hole wall may be inclined more than 1.5 °. A preferable inclination angle is in the range of 0 to 10 °.

  The small-diameter cylindrical portion 15a of the outer pipe 15 is inserted into the lower through-hole 43 of the engine bracket 3 formed in this way from below, and the large-diameter cylindrical portion 15c until the flange portion 15d hits the lower end of the casing portion 3a. As shown in FIG. 7, the large-diameter cylindrical portion 15c is press-fitted into the large-diameter portion 43c and is narrowed, so that the small-diameter cylindrical portion 15a has an upper end portion 15e with the inner peripheral surface of the small-diameter portion 43a. As it goes upward, it expands outward in the cylinder radial direction so as to close the gap. Thereby, in the liquid filled type vibration isolator 1 of the present embodiment, the upper end portion 35b of the rubber elastic body 35 formed so as to wind up the upper end portion 15e of the outer pipe 15 (not shown in FIG. 7). However, the sealability between the engine bracket 3 and the main spring portion 5 is enhanced by being pressed against the inner peripheral surface of the small diameter portion 43a.

  Here, since the small-diameter cylindrical portion 15a is deformed so as to expand outward as it goes upward, as shown in FIG. 7, between the outer peripheral surface of the small-diameter cylindrical portion 15a and the inner peripheral surface of the small-diameter portion 43a. Thus, a space 41 having a substantially triangular cross section is formed. Therefore, in the liquid-filled vibration isolator 1 of the present embodiment, in order to further improve the sealing performance, as shown in FIG. 8A, the upper and lower portions projecting outward in the cylinder radial direction on the outer peripheral surface of the small diameter cylinder portion 15a. A lower seal rubber portion 35 c provided with a three-stage seal lip 35 d and thicker toward the bottom is formed integrally with the rubber elastic body 35.

  Thus, by forming the lower seal rubber portion 35c that becomes thicker as it goes downward, the large-diameter cylindrical portion 15c is press-fitted into the large-diameter portion 43c, and as the small-diameter cylindrical portion 15a goes upward, the cylindrical radial direction When expanded outward, as shown in FIG. 8B, the lower seal rubber portion 35c forms a space 41 having a substantially triangular cross section between the outer peripheral surface of the small diameter cylindrical portion 15a and the inner peripheral surface of the small diameter portion 43a. In addition, since the seal lip 35d is pressed against the inner peripheral surface of the small diameter portion 43a, the sealing performance between the engine bracket 3 and the main spring portion 5 is further enhanced.

  As described above, in the liquid-filled vibration isolator 1 of the present embodiment, the seal by expanding outward in the cylinder radial direction as the small-diameter cylindrical portion 15a of the outer pipe 15 goes upward, and the lower seal rubber portion 35c have a small diameter. By providing a two-stage seal called a seal by filling a space 41 having a substantially triangular cross section between the outer peripheral surface of the cylindrical portion 15a and the inner peripheral surface of the small diameter portion 43a, the through hole 13 of the engine bracket 3 is provided with an outer It is possible to enhance the sealing performance between the both 3 and 15 while having a structure in which the pipe 15 is press-fitted.

  Further, the sealing is not performed by pressing the upper end portion 15e of the rubber elastic body 35 against the lower surface of the orifice plate 7, but by pressing the upper end portion 15e of the rubber elastic body 35 against the inner peripheral surface of the small diameter portion 43a. Therefore, by pressing the outer pipe 15, it is possible to reliably avoid closing one end of the orifice passage 7 a that opens toward the pressure receiving chamber 31 a below the liquid chamber 31. .

-Stopper rubber-
As shown in FIGS. 2, 9 and 10, the stopper rubber 11 includes a substantially rectangular stopper main body 51 held on the outer side surface (mounting base portion 3 c) of the casing portion 3 a, and the stopper main body 51. It has a pair of upper and lower stopper mounting portions 61, 71 extending from the upper end portion and the lower end portion to the inside in the cylinder radial direction, and is formed in a substantially U-shaped cross section. Thus, the stopper rubber 11 having a substantially U-shaped cross section is attached to the casing portion 3a so that the casing portion 3a is sandwiched between the upper and lower pair of stopper attaching portions 61 and 71 in the cylinder axis direction.

  Four outer ridges (projections) 51a extending in a direction perpendicular to the vertical direction and the front-rear direction (hereinafter referred to as the left-right direction) so as to form three outer grooves 51b on the outer surface of the stopper main body 51. Are formed on the inner side surface of the stopper main body 51 so as to form three inner grooves 51d extending in the left-right direction.

  Further, the upper stopper mounting portion 61 is formed with four protrusions 61b extending in the left-right direction so as to form three grooves 61c on the upper surface thereof, while the concave groove portion 3d of the casing portion 3a is formed on the lower surface thereof. An upper ridge portion 61a having a substantially inverted trapezoidal cross section and extending in the left-right direction and projecting downward is formed. On the other hand, on the upper surface of the lower stopper mounting portion 71, a lower convex strip portion 71 a that fits in the concave groove portion 3 e of the casing portion 3 a and extends in the left-right direction and protrudes upward is formed. Yes.

  Further, as shown in FIGS. 2 and 11, the stopper rubber 11 has a substantially rectangular main body portion 12 a corresponding to the stopper main body portion 51, and an inner side in the cylinder radial direction from the upper end portion and the lower end end portion of the main body portion 12 a. A metal reinforcing member 12 having a substantially U-shaped cross section having extending portions 12c and 12d extending therein is embedded. A rectangular opening 12b is formed in the main body 12a of the reinforcing member 12, and the main body 12a of the reinforcing member 12 has a substantially rectangular frame shape.

  Then, the stopper rubber 11 is formed by fitting the upper and lower convex ridges 61a and 71a protruding from the upper and lower stopper attaching portions 61 and 71 into the concave grooves 3d and 3e of the casing 3a. Thus, the stopper body 51 is attached to the casing 3a, whereby the stopper main body 51 is held on the outer side surface (mounting base 3c) of the casing 3a.

  Here, since an inner protrusion 51c that protrudes inward in the cylinder radial direction is formed on the inner side surface of the stopper main body 51, when the stopper rubber 11 is attached to the casing part 3a, the inner protrusion 51c acts to push the outer surface of the mounting base 3c inward in the cylinder radial direction. For this reason, since the stopper main body 51 is pushed outward in the cylindrical radial direction by the reaction force from the mounting base 3c, the upper and lower ridges 61a and 71a fitted in the grooves 3d and 3e are It will be pulled outward in the cylinder radial direction. As a result, the upper and lower ridges 61a and 71a projecting from the upper and lower stopper mounting portions 61 and 71 and the inner ridges 51c projecting inward in the cylinder radial direction are as if the casing 3a. The stopper rubber 11 is firmly attached to the casing portion 3a because it acts so as to be sandwiched in the cylinder radial direction. Therefore, even when the separate stopper rubber 11 is attached to the outer side surface of the engine bracket 3, the noise generated by the separation and contact between the inner side surface of the stopper rubber 11 and the outer side surface of the engine bracket 3 is repeated. Can be suppressed.

  Further, since the inner protrusion 51c is formed so as to form the inner groove 51d on the inner surface of the stopper main body 51, the presence of the inner groove 51d causes the inner surface of the stopper main body 51 to be attached to the mounting base. The contact area with the outer surface of the part 3c will decrease. Thereby, even when the inner side surface of the stopper rubber 11 and the outer side surface of the mounting base portion 3c are rubbed, generation of abnormal noise can be suppressed.

  Furthermore, since the opening 12b is formed in the main body 12a of the reinforcing member 12 embedded in the stopper main body 51, the stopper main body 51 is located at a portion corresponding to the opening 12b in the stopper main body 51. The reinforcing member 12 is not divided into the inner side and the outer side in the cylinder radial direction, and an appropriate rubber volume is secured. In addition, since the stopper main body 51 is formed with outer and inner grooves 51b and 51d extending in the left-right direction, the stopper main body 51 is deformed by crushing (filling) these grooves 51b and 51d. It is easy. In other words, even if the outer and inner protrusions 51a and 51c are deformed so as to swell up and down in response to a load, the bulge is absorbed by the outer and inner grooves 51b and 51d, so that the stopper main body 51 is deformed. It is easy to do. Thus, since the stopper main body 51 has an appropriate rubber volume and is formed in a shape that is easily deformed, it exhibits a soft spring characteristic.

  Here, in the conventional one in which the rubber elastic body 135 and the stopper rubber 111 are simultaneously molded on the engine bracket 103, when the stopper rubber 111 is deformed and the groove is filled, as shown by a white arrow in FIG. Since the stopper rubber 111 is deformed so as to escape in the vertical direction, the elastically supported power plant may be displaced too much. On the other hand, in the stopper rubber 11 according to the present embodiment, when the outer and inner protrusions 51a and 51c are deformed and the outer and inner grooves 51b and 51d are filled, the portion corresponding to the opening 12b in the stopper main body 51. However, even when trying to deform so as to escape in the cylinder axis direction, as shown by the white arrow in FIG. 12B, the deformation is suppressed by the main body 12a of the frame-shaped reinforcing member 12, so that the stopper main body 51 will exhibit a hard spring characteristic.

  FIG. 13 is a graph showing a load-deflection curve of the stopper rubber obtained from the simulation. The solid line in the figure shows a load-deflection curve when a load is applied to the stopper rubber 11 of the present embodiment, and the broken line in the figure shows a load applied to a conventional stopper rubber simultaneously molded on the engine bracket. A load-deflection curve is shown for each case. From the figure, the stopper rubber 11 of the present embodiment exhibits a soft spring characteristic in the region where the input load is small (region A), as in the case of the conventional stopper rubber, while the input rubber increases as the input load increases (region B). It has been confirmed that the spring characteristics are harder than the stopper rubber.

  As described above, it has a two-stage characteristic including a region (region A) that is greatly deformed and absorbs an impact when a load is input, and a region (region B) that is not significantly deformed even when a load is input and suppresses displacement. The stopper rubber 11 can be realized.

-Effect-
According to the present embodiment, since the main spring portion 5 and the stopper rubber 11 and the engine bracket 3 are separated, the plurality of main spring portions 5 and the stopper rubber 11 can be formed by one molding.

  Further, since the reinforcing member 12 having a substantially U-shaped cross section is embedded in the stopper rubber 11 having a substantially U-shaped cross section, the durability of the stopper rubber 11 can be improved.

  Further, since the upper and lower ridges 61a and 71a and the inner ridge 51c act as if the casing 3a is sandwiched in the cylinder radial direction, the stopper rubber 11 is firmly attached to the casing 3a. Further, since the inner groove 51d is formed on the inner side surface of the stopper main body 51, the contact area between the inner side surface of the stopper main body 51 and the mounting base portion 3c is reduced. As a result, it is possible to suppress abnormal noise that occurs when the inner side surface of the stopper rubber 11 and the outer side surface of the engine bracket 3 are repeatedly separated and contacted or rubbed.

(Other embodiments)
The present invention is not limited to the embodiments, and can be implemented in various other forms without departing from the spirit or main features thereof.

  In the above embodiment, the cylinder axis direction of the outer pipe 15 is directed in the vertical direction. However, the present invention is not limited to this, and the cylinder axis direction of the outer pipe 15 may be inclined according to the application. Contrary to the form, the diaphragm 9 may be positioned on the lower side.

  Moreover, in the said embodiment, although the protrusion part of the inner side and the outer surface of the stopper main-body part 51 was made into the protrusion part extended in the left-right direction, as long as it is a protrusion part which protrudes so that a groove part may be formed, it is not restricted to this, For example, a dimple-shaped protrusion may be used.

  Furthermore, in the said embodiment, although the opening part was made into the rectangle, it is not restricted to this, For example, it is good also as a circle.

  Moreover, in the said embodiment, although the outer pipe 15 made from an aluminum alloy was used, it is not restricted to this, For example, you may use an iron outer pipe.

  As described above, the above-described embodiment is merely an example in all respects and should not be interpreted in a limited manner. Further, all modifications and changes belonging to the equivalent scope of the claims are within the scope of the present invention.

  As described above, the present invention is useful for a liquid-filled vibration isolator equipped with a bracket used for mounting an automobile engine or the like.

1 Liquid-filled vibration isolator 3 Engine bracket (bracket)
3a Casing part 3b Mounting part 3d Groove part (concave part)
3e Concave groove (recess)
5 Main spring part 11 Stopper rubber (stopper part)
12 reinforcement member 12a body part 12b opening part 12c extension part 12d extension part 13 through hole 15 outer pipe (cylinder)
25 Inner plate (mounting bracket)
31 Liquid chamber 35 Rubber elastic body 51 Stopper main body 51a Outer protrusion (protrusion)
51b Outer groove (groove)
51c Inner ridge (projection)
51d Inner groove (groove)
61 Upper stopper mounting portion 61a Upper ridge (convex)
71 Lower stopper mounting portion 71a Lower ridge (convex)

Claims (2)

A main spring part in which a mounting bracket attached to the vehicle body and a cylinder are connected by a rubber elastic body, a substantially cylindrical casing part having a through hole, and an attachment part for attaching the casing part to the engine side are integrated. And a volume-variable liquid chamber having the rubber elastic body and the inner peripheral surface of the casing part as a part of the wall part by press-fitting the cylindrical body into the through-hole. A liquid-filled vibration isolator,
Further comprising a rubber stopper attached to the casing part from the outside in the cylinder radial direction,
The stopper portion is a substantially rectangular stopper main body held on the outer side surface of the casing portion, and a pair of upper and lower stopper mounting portions extending inward in the cylinder radial direction from both ends of the stopper main body in the cylinder axis direction, And is attached to the casing part so as to sandwich the casing part in the cylinder axis direction by the pair of upper and lower stopper attaching parts.
The stopper mounting portion is formed with a convex portion that protrudes inward in the cylindrical axis direction, and is fitted to a concave portion formed at both cylindrical axial end portions of the casing portion. Is provided with a protruding portion that protrudes inward in the cylinder radial direction so as to form a groove. The liquid-filled vibration isolator according to claim 1,
On the outer side surface of the stopper main body part, a protruding part that protrudes outward in the cylinder radial direction so as to form a groove part is formed,
The stopper portion has a substantially rectangular main body portion corresponding to the stopper main body portion, and a pair of upper and lower extending portions extending inward in the cylinder radial direction from both end portions in the cylinder axis direction of the main body portion. A reinforcing member formed in a letter shape is embedded,
A liquid-filled vibration isolator having an opening formed in the main body of the reinforcing member.

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