JP5490566B2 - Suspension support - Google Patents

Description

  The present invention relates to a suspension support for elastically coupling a piston rod of a shock absorber in a suspension mechanism of a vehicle such as an automobile to a vehicle body.

  2. Description of the Related Art Conventionally, in an automobile suspension mechanism, in order to suppress vibration transmission from the wheel side to the vehicle body side, an inner member into which the upper end portion of the piston rod of the shock absorber is inserted and fixed, and an outer periphery of the inner member are surrounded. A suspension support including an outer member attached to the side and an annular elastic member interposed between the inner member and the outer member is used.

  As the elastic member, a rubber material is generally used, but recently, an elastic foam material having an open cell structure such as urethane foam has been tried (see Patent Document 1 below). Due to the material properties of urethane foam, it is possible to increase the damping performance while suppressing the dynamic magnification as compared with rubber materials, and to improve riding comfort.

  As a suspension support having such a foamed urethane molded body as an elastic member, in Patent Document 2, as shown in FIG. 9, the elastic member 100 is composed of a rubber elastic portion 102 made of a rubber material and a foamed urethane molded body. By combining with the foamed resin elastic part 104, it is possible to reduce the precompression ratio of the foamed urethane molded product while maintaining the static spring constant, thereby achieving both static spring constant and high damping characteristics. Is disclosed.

JP 2003-184937 A JP 2009-264553 A

  In the configuration disclosed in Patent Document 2, the elastic member 100 (that is, rubber made of a rubber material) having a different material is disposed between the flange portion 108 of the inner member 106 and the upper and lower wall portions 112 and 114 of the outer member 110. Since the elastic part 102 and the foamed resin elastic part 104) made of urethane foam are sandwiched, the number of manufacturing steps increases. Further, since the thin-walled portion 102A is formed in the rubber elastic portion 102 that is vulcanized and bonded to the inner member 106, there is a concern about durability problems such as peeling.

  An object of the present invention is to solve the above problems and improve productivity and durability in a suspension support using an elastic member made of a foamed resin molded body such as urethane foam.

A suspension support according to the present invention is an inner member into which an upper end portion of a piston rod of a shock absorber is inserted and fixed. An outer member that surrounds the outer periphery of the inner member and is attached to the vehicle body side, the outer member having an upper side wall portion and a lower side wall portion that are opposed to each other at an interval above and below the flange portion, the inner member, An annular elastic member interposed between the outer member and the upper elastic portion sandwiched between the flange portion and the upper side wall portion, and sandwiched between the flange portion and the lower side wall portion. And an elastic member having a lower elastic portion. And at least one elastic part of the upper elastic part and the lower elastic part is made of the same material as the first elastic part and the first elastic part, and is lower than the first elastic part. It has at least a two-layer structure with a second elastic part made of a foamed resin molded body having a foaming rate or an unfoamed resin molded body, and the thickness ratio of the first elastic part to the second elastic part It was changed in the circumferential direction. Then, in the invention according to claim 1, wherein with the two opposite positions across the inner member is set higher thickness ratio of the first elastic part in a first direction perpendicular to the axis, the first axis-perpendicular direction The thickness ratio of the second elastic portion is set high at two locations facing each other across the inner member in the second axis perpendicular direction to the first axis.

  According to the above configuration, the first elastic portion having a high expansion rate is a portion that mainly ensures damping characteristics, and the low expansion rate or the non-foamed second elastic portion is a portion that mainly maintains a static spring constant. Therefore, by changing the thickness ratio of the first elastic portion and the second elastic portion in the circumferential direction, the damping characteristic is mainly increased at the portion where the thickness of the first elastic portion is increased, and the thickness of the second elastic portion is increased. A static spring constant can be secured mainly at the site, and it is easy to achieve both static spring constant and high damping characteristics. In addition, by changing the thickness ratio in the circumferential direction, it is possible to give directionality to characteristics such as the twisting performance.

  Furthermore, since the first elastic part and the second elastic part are formed of the same material, both can be produced integrally, and manufacturing including the assembly process is facilitated, and the same material is used. The first elastic portion and the second elastic portion can be bonded without using an adhesive, and there is no shaving due to friction between them, and durability can be improved. Therefore, productivity and durability can be improved while pursuing the above-described excellent vibration isolation performance.

The longitudinal cross-sectional view of the suspension support which concerns on 1st Embodiment (cross-sectional view equivalent to the II line of FIG. 4) Exploded longitudinal sectional view of the suspension support Side view of upper elastic part of suspension support Plan view of the upper elastic part Side view of the upper elastic part in the second embodiment Side view of the upper elastic part in the third embodiment The top view of the upper side elastic part in 3rd Embodiment Vertical section of suspension support according to the fourth embodiment Vertical section of conventional suspension support

  The suspension support 10 according to the first embodiment will be described with reference to FIGS. The suspension support 10 is a strut mount for an automobile, and includes a metal inner member 12 into which an upper end portion 1A of a shock absorber piston rod 1 is inserted and fixed, and a metal outer member that surrounds the outer periphery thereof and is attached to the vehicle body panel 2. The member 14 includes an annular elastic member 16 that is interposed between the inner member 12 and the outer member 14 and supports the inner member 12 against the outer member 14 in a vibration-proof manner. The suspension support 10 is provided with the axial direction X of the piston rod 1 as the vertical direction.

  The inner member 12 includes a cylindrical inner cylinder portion 18 into which the upper end portion 1A of the piston rod 1 is inserted from below, and a ring plate that protrudes to the outer side Yo in the direction perpendicular to the axis of the piston rod 1 at the upper end portion of the inner cylinder portion 18. And a flange portion 20 having a shape.

  The outer member 14 encloses the elastic member 16 and concentrically surrounds the inner member 12, and the both ends of the peripheral wall portion 22 in the axial direction X are inwardly Yi in the direction perpendicular to the axis Y. The upper side wall part 24 and the lower side wall part 26 which are formed and clamp the elastic member 16 in the axial direction X are provided, and are formed in a container shape that accommodates the elastic member 16 therein. The peripheral wall portion 22 surrounds the outer periphery of the flange portion 20 at an interval. The upper side wall portion 24 and the lower side wall portion 26 are disposed to face the upper surface 20A and the lower surface 20B of the flange portion 20 with a space therebetween, both form a ring plate shape, and have a circular opening 28 at the center. , 30 are provided.

  In this example, the outer member 14 includes a first flange-shaped first outer member 32 that opens downward, and a flat plate-like second outer member 34 that covers the lower surface opening. 22 and the upper side wall part 24 are formed, and the lower side wall part 26 is formed by the second outer member 34.

  As shown in FIG. 2, the first outer member 32 has an outer diameter that is substantially constant in the axial direction X (specifically, a tapered wall that is slightly tapered toward the top), and an inward Yi at the upper end thereof. The upper wall portion 24 extends in a flange shape, and the upper mounting flange 36 extends to the outer side Yo at the lower end of the peripheral wall portion 22. The second outer member 34 has a central portion around the opening 30 as the lower side wall portion 26, and a lower mounting flange 38 is provided on the outer periphery thereof. Then, the outer member 14 is fixed to the vehicle body panel 2 by overlapping the upper mounting flange 36 and the lower mounting flange 38 on the lower surface of the vehicle body panel 2 and fastening them with the bolts 3 and nuts 4. It is configured. A holding fitting 40 for holding a bound stopper (not shown) is caulked and fixed to the opening 30 of the lower side wall portion 26.

  The elastic member 16 is opened inward Yi so that the entire shape of the elastic member 16 wraps the flange portion 20 of the inner member 12 from the outside, that is, covers the upper surface 20A, the lower surface 20B, and the outer peripheral surface 20C of the flange portion 20. It has a U-shaped cross section.

  In this example, the elastic member 16 is a two-piece type that is divided into two on the upper and lower sides of the flange portion 20. Specifically, the elastic member 16 includes an annular upper elastic part 42 held between the flange part 20 and the upper side wall part 24 in the axial direction X, and the flange part 20 and the lower side wall part 26. It comprises an annular lower elastic portion 44 that is sandwiched and held in the axial direction X, and these are separately molded by molding, and are integrally assembled between the inner member 12 and the outer member 14.

  The upper elastic portion 42 includes a first elastic portion 46 made of a foamed urethane molded body (polyurethane foam) having an open-cell structure, and a foamed urethane molded body having an open-cell structure having a lower foaming rate than this, or an unfoamed solid urethane It is formed in an upper and lower two-layer structure with a second elastic portion 48 made of a molded body. More specifically, between the flange part 20 and the upper side wall part 24, the second elastic part 48 is on the flange part 20 side (ie, the lower side), and the first elastic part 46 is on the upper side wall part 24 side (ie, the lower side). Upper and lower two-layer structure.

  Similarly for the lower elastic portion 44, a first elastic portion 46 made of a foamed urethane molded body (polyurethane foam) having an open cell structure and a foamed urethane molded body having an open cell structure having a lower foaming rate than this, or It is formed in an upper and lower two-layer structure with a second elastic portion 48 made of an unfoamed solid urethane molded body. More specifically, between the flange portion 20 and the lower wall portion 26, the second elastic portion 48 is on the flange portion 20 side (ie, the upper side), and the first elastic portion 46 is on the lower wall portion 26 side (ie, the lower side). Side)).

The foaming rate of the second elastic portion 48 is not particularly limited as long as it is smaller than the foaming rate of the first elastic portion 46, but preferably these densities (bulk density) are set as follows. That is, it is preferable that the density of the first elastic portion 46 is 0.4 to 0.7 g / cm ³ and the density of the second elastic portion 48 is 0.8 to 1.2 g / cm ³ without being pre-compressed. Preferably, it is cm ³ , and the difference between the two is preferably 0.3 g / cm ³ or more. In order to increase the density difference between the two, it is more preferable that the second elastic portion 48 is an unfoamed solid urethane molded body.

  The first elastic portion 46 of the upper elastic portion 42 is an annular member that is clamped and held in the axial direction X between the upper surface of the second elastic portion 48 and the lower surface of the upper side wall portion 24. It is integrally provided on the upper side and is sandwiched between the flange portion 20 and the upper side wall portion 24 via the second elastic portion 48. The first elastic portion 46 of the lower elastic portion 44 is an annular member that is sandwiched and held in the axial direction X between the lower surface of the second elastic portion 48 and the upper surface of the lower side wall portion 26, and the second elastic portion 48. And is sandwiched between the flange portion 20 and the lower side wall portion 26 via the second elastic portion 48.

  The second elastic portion 48 of the upper elastic portion 42 is an annular member that is sandwiched and held in the axial direction X between the upper surface 20A of the flange portion 20 and the lower surface of the first elastic portion 46. A fitting recess 50 having a circular shape in plan view into which 20 is fitted is provided. The second elastic portion 48 of the lower elastic portion 44 is an annular member that is clamped and held in the axial direction X between the lower surface 20B of the flange portion 20 and the upper surface of the first elastic portion 46. A circular fitting recess 50 in which the portion 20 is fitted is provided. Accordingly, as shown in FIG. 1, in a state where the upper elastic portion 42 and the lower elastic portion 44 are combined, the upper and lower second elastic portions 48, 48 are integrated so as to wrap the flange portion 20. 20 is in contact with the upper surface 20A, the lower surface 20B, and the outer peripheral surface 20C.

  The outer peripheral surface 48A of the second elastic portion 48 is surrounded by the peripheral wall portion 22 of the outer member 14 without the first elastic portion 46 interposed. In this example, the outer peripheral surface 48A of the second elastic portion 48 is provided. Is in contact with the inner peripheral surface of the peripheral wall portion 22. Further, the second elastic portion 48 does not reach the upper and lower wall portions 24 and 26 of the outer member 14, and an interface 52 is provided between the second elastic portion 48 and the first elastic portion 46 over the entire circumference in the circumferential direction. . That is, the upper elastic part 42 and the lower elastic part 44 are each formed in an upper and lower two-layer structure over the entire circumference.

  In this embodiment, in each of the upper elastic portion 42 and the lower elastic portion 44, the thickness ratio of the first elastic portion 46 and the second elastic portion 48 (that is, the ratio of the height in the axial direction X) is the circumferential direction. It is changed by. Specifically, as shown in FIGS. 3 and 4, a portion 54 in which the thickness ratio of the first elastic portion 46 is set high and a portion 56 in which the thickness ratio of the second elastic portion 48 is set high are in the circumferential direction C. In this example, the part 54 is provided at six positions on the circumference at predetermined intervals, and the part 56 is interposed therebetween. The interface 52 between the first elastic portion 46 and the second elastic portion 48 is formed in an uneven shape (step shape) in the circumferential direction C.

  In the upper elastic portion 42, the first elastic portion 46 and the second elastic portion 48 are bonded and integrated by molding. Specifically, for example, the first elastic portion 46 is integrally foam-molded on the upper surface of the second elastic portion 48 molded in advance, so that the interface 52 between the second elastic portion 48 and the first elastic portion 46 is bonded. Integrated. Similarly, for the lower elastic portion 44, the first elastic portion 46 and the second elastic portion 48 are bonded and integrated by molding. For example, the details of the second elastic portion 48 molded in advance are provided. The interface 52 between the second elastic part 48 and the first elastic part 46 is bonded and integrated by integrally foaming the first elastic part 46 on the lower surface. By molding in this way, the interface 52 is integrated with a certain degree of adhesive force without using an adhesive. The first elastic portion 46 can be molded first, and then the second elastic portion 48 can be integrally molded. In this case, the foaming rate is increased by the injection pressure of the molding material when the second elastic portion 48 is molded. Since the first elastic portion 46 having a high height may be deformed, the second elastic portion 48 is preferably formed first. Further, the upper elastic portion 42 and the lower elastic portion 44 are formed in the same shape, and the parts are shared.

  The upper elastic portion 42 and the lower elastic portion 44 thus formed are respectively attached to the inner member 12 from above and below, and are attached to the first outer member 32 and the second outer member 34 of the outer member 14. The mounting flanges 36 and 38 of both members are overlapped on the lower surface of the vehicle body panel 2 and fastened and fixed using bolts 3 and nuts 4, and the upper end 1 </ b> A of the piston rod 1 is used as an inner member using nuts 5. As shown in FIG. 1, the suspension support 10 is assembled by being inserted and fixed to 12.

  As a result, the elastic member 16 is held in a state compressed in the axial direction X by the outer member 14 (preliminarily compressed state). At that time, the first elastic portion 46 having a high expansion rate is pre-compressed at a higher compression rate than the second elastic portion 48 having a low expansion rate. However, even in the pre-compressed state, the second elastic portion 48 has a smaller foaming rate, that is, a higher density.

  In the suspension support 10 configured as described above, the first elastic portion 46 having a high expansion ratio is a portion that mainly ensures damping characteristics, and the low expansion ratio or the non-foamed second elastic portion 48 mainly maintains a static spring constant. Become. Therefore, by changing the thickness ratio between the first elastic portion 46 and the second elastic portion 48 in the circumferential direction C, the damping characteristic is mainly increased in the portion 54 where the thickness of the first elastic portion 46 is increased. The static spring constant can be secured mainly at the portion 56 where the thickness is increased. Specifically, by increasing the thickness of the first elastic portion 46 having a high foaming rate, it is possible to improve the damping characteristics and reduce the dynamic spring constant, which leads to an improvement in vehicle riding comfort. Further, the static spring constant can be improved by increasing the thickness of the second elastic portion 48 having a low foaming rate, which leads to improvement in vehicle handling stability. Therefore, by changing the thickness ratio between the first elastic portion 46 and the second elastic portion 48 in the circumferential direction C, both low dynamic magnification and high damping characteristics can be achieved.

  In addition, since the first elastic portion 46 and the second elastic portion 48 are formed of the same material called polyurethane, both can be integrally molded as described above. It becomes easy. In addition, since the same material is used, the first elastic portion 46 and the second elastic portion 48 can be bonded without using an adhesive, so that the manufacturing cost can be reduced and the manufacturing can be performed without using an adhesive. It becomes easy.

  Further, by bonding and integrating the first elastic portion 46 and the second elastic portion 48 made of the same material, durability can be improved without being scraped by friction between the two. Further, since vulcanization adhesion to the inner member as in the prior art is not required, there is no fear of peeling to the inner member 12, and durability is further improved.

  Further, by changing the thickness ratio of the first elastic portion 46 and the second elastic portion 48 in the circumferential direction C, the interface 52 between the two becomes uneven and the bonding area is increased. The adhesive force between the elastic part 46 and the second elastic part 48 can be further improved.

  FIG. 5 relates to a suspension support according to the second embodiment. The second embodiment is different from the first embodiment in the configuration of the elastic member 16.

  In this example, in the upper elastic portion 42 and the lower elastic portion 44 of the elastic member 16, the first elastic portion 46 having a high foaming rate is formed to protrude outward in the axial direction X at a plurality of locations in the circumferential direction C. This also changes the thickness ratio of the first elastic portion 46 in the circumferential direction. More specifically, the first elastic portion 46 is formed with a protruding portion 60 that protrudes outward in the axial direction X at a portion 54 where the thickness ratio of the first elastic portion 46 is set high.

  When the overhanging portion 60 is assembled as a suspension support between the inner member 12 and the outer member 14, it is flattened by being compressed by the upper wall portion 24 or the lower wall portion 26 of the outer member 14. However, a state in which the main body portion of the first elastic portion 46 is separated from the upper and lower wall portions 24 or 26 by the elastic portion 42 or 44 on the side opposite to the compression direction due to large amplitude vibration input in the axial direction X. Even when it becomes, since it is possible to perform further expansion / contraction deformation by the overhanging portion 60, the attenuation characteristic can be improved accordingly. Other configurations and operational effects are the same as those of the first embodiment, and a description thereof will be omitted.

  6 and 7 relate to the suspension support according to the third embodiment. In the third embodiment, the configuration of the elastic member 16 is different from that of the first embodiment.

  In this example, the upper elastic portion 42 and the lower elastic portion 44 are set to have a high thickness ratio of the first elastic portion 46 at two locations facing each other across the inner member 12 in the first axis-perpendicular direction Y1. The thickness ratio of the second elastic portion 48 is set high at two locations facing each other across the inner member 12 in the second axis perpendicular direction Y2 perpendicular to the first axis orthogonal direction Y1. In other words, in this example, the upper and lower elastic parts 42 and 44 are each composed of four regions on the circumference, and the two parts 54 in which the thickness of the first elastic part 46 is set high are opposed to each other in the first axis-perpendicular direction Y1. In addition, the region 56 in which the thickness of the second elastic portion 48 is set high is set in two regions opposite to each other in the second axis-perpendicular direction Y2.

  Thereby, for example, the first axis perpendicular direction Y1 is set to be the vehicle longitudinal direction, and the second axis perpendicular direction Y2 is set to be the vehicle lateral direction, so that the twist input in the vehicle longitudinal direction Y1 is performed. As a result, the ride comfort can be improved by reducing the rigidity, and the steering stability can be improved by increasing the rigidity with respect to the twisting input in the vehicle left-right direction Y2. Thus, by changing the thickness ratio between the first elastic portion 46 and the second elastic portion 48 in the circumferential direction C, the twisting characteristic can be given directionality. Other configurations and operational effects are the same as those of the first embodiment, and a description thereof will be omitted.

  FIG. 8 shows a suspension support according to the fourth embodiment. The fourth embodiment is different from the first embodiment in the configuration of the lower elastic portion 44.

  In this example, in the lower elastic portion 44, the thickness ratio of the first elastic portion 46 and the second elastic portion 48 is constant without being changed in the circumferential direction C. More specifically, in the lower elastic portion 44, the thickness ratio of the low-foamed or non-foamed second elastic portion 48 is set to be large over the entire circumference, whereby the rebound side (that is, the lower side of the inner member 12). The static spring constant at the time of displacement to) is set larger. Therefore, the steering stability can be further improved without impairing the ride comfort. Other configurations and operational effects are the same as those of the first embodiment, and a description thereof will be omitted.

  In the above embodiment, both the upper elastic portion 42 and the lower elastic portion 44 have a two-layer structure, but either one may have a one-layer structure. For example, in the fourth embodiment, the lower elastic portion 44 may be entirely formed of a solid urethane molded body instead of a two-layer structure having a constant thickness ratio, thereby further increasing the rigidity on the rebound side. You can also. Further, the upper elastic portion 42 and the lower elastic portion 44 may have three or more layers by providing an additional layer in addition to the two layers of the first elastic portion 46 and the second elastic portion 48.

  In the above embodiment, the two-piece type elastic member has been described. However, the present invention also relates to a one-piece type in which an elastic member made of a urethane material is integrally molded so as to wrap the flange portion of the inner member, for example. The same can be applied.

  Moreover, in the said embodiment, although the thickness of the 1st elastic part 46 is set larger than the 2nd elastic part 48 in the site | part 54 which set the thickness ratio of the 1st elastic part 46 high, in this invention Setting the thickness ratio higher is not limited to such a mode, and includes a case where the thickness ratio of the first elastic portion 46 is set higher than other circumferential portions. The same applies to the portion 56 where the thickness ratio of the second elastic portion 48 is set high.

  In the present invention, the same material for the first elastic part and the second elastic part is the same as the basic polymer type, for example, polyurethane is used as the polymer for both the first elastic part and the second elastic part. It is intended to be, and is not intended to be the same up to the specific configuration of the polyurethane. Preferably, in order to enhance the adhesive effect at the interface between the first elastic part and the second elastic part and to reduce the cost by using a common material, the first elastic part and the second elastic part differ only in the foaming rate. It is to use materials (that is, materials of the same composition that differ only in the amount or presence or absence of the blowing agent).

  In addition, although not described one by one, various modifications can be made without departing from the spirit of the present invention.

DESCRIPTION OF SYMBOLS 1 ... Histone rod, 1A ... Upper end part, 2 ... Body panel,
10 ... Suspension support,
12 ... Inner member, 14 ... Outer member, 16 ... Elastic member,
20 ... Flange, 24 ... Upper wall, 26 ... Lower wall,
42 ... upper elastic part, 44 ... lower elastic part,
46 ... 1st elastic part, 48 ... 2nd elastic part,
54... Part where the thickness ratio of the first elastic part is set high 56. Part where the thickness ratio of the second elastic part is set high X... Axial direction, Y ... axis perpendicular direction, Yo ... axis orthogonal direction outward Y1. Y2 direction perpendicular to the axis Y2 ... second axis perpendicular direction C ... circumferential direction

Claims (2)

An inner member in which an upper end portion of a piston rod of a shock absorber is inserted and fixed; and an inner member provided with a flange portion protruding outward in a direction perpendicular to the axis of the piston rod;
An outer member that surrounds the outer periphery of the inner member and is attached to the vehicle body, the outer member having an upper side wall portion and a lower side wall portion that are opposed to each other at an interval above and below the flange portion;
An annular elastic member interposed between the inner member and the outer member, between the upper elastic portion, the flange portion, and the lower wall portion sandwiched between the flange portion and the upper wall portion. An elastic member having a lower elastic part sandwiched between,
With
At least one elastic part of the upper elastic part and the lower elastic part is composed of a first elastic part made of a foamed resin molded body and the same material as the first elastic part, and has a lower foaming rate than the first elastic part. A foamed resin molded body or a non-foamed resin molded body and a second elastic part, which are at least two layers above and below, and the thickness ratio between the first elastic part and the second elastic part is the circumferential direction of the elastic member The thickness ratio of the first elastic portion is set high at two locations opposite to each other across the inner member in the direction perpendicular to the first axis, and the direction perpendicular to the first axis is set. The suspension support according to claim 1, wherein a thickness ratio of the second elastic portion is set to be high at two locations facing each other across the inner member in a direction perpendicular to the second axis. The said 1st elastic part consists of a foaming urethane molded object, The said 2nd elastic part consists of a foaming urethane molded object or a solid urethane molded object of low foaming rather than the said 1st elastic part, It is characterized by the above-mentioned. Suspension support.

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