Vehicle rear suspension mounting structure

Abstract: Disclosed is a vehicle rear suspension mounting structure for mounting, to a vehicle body(B), the other end of a rear suspension(10) comprising a suspension link(16), one end of which is coupled to a wheel support member(30) for rotatably supporting a vehicle wheel(RR) and which extends substantially in a longitudinal direction of the vehicle body(B), including a vehicle body coupling end(16a) formed on the other end of the suspension link(16), a link bracket(50) for supporting the vehicle body coupling end(16a), and a joint member(60) for joining the link bracket(50) to a rear quarter panel(38) constituting a rear wheel house portion(14).

Description: The invention relates to a vehicle rear suspension mounting structure according to the preamble of claim 1. Such a mounting structure is already disclosed in DE-C-1 013 534. This preknown design represents a very old conventional rear suspension of a single link suspension type, in which the suspension link having a wheel support member on its distal end is held by means of an axis member which is rotatably attached to link brackets. The joint means integrally made with the link bracket is attached to the rear wheel house inner portion thus maintaining mechanical strength of the link bracket. Any further features for assuring sufficient support rigidity, in particular in case of a collision of a vehicle, are not disclosed. GB-A-2 001 915 discloses a vehicle rear structure which is well known among persons skilled in the art. In particular, Fig. 33 shows a cross-sectional view of the rear wheel housing portion, a rear quarter panel and a rear wheel housing inner portion, which are welded together, and a fly neck bracket and a rear pillar portion are welded with the rear quarter panel in order to form closed space. However, there is no disclosure or suggestion how the rear wheel suspension is to be mounted nor a disclosure concerning the construction for mounting rear wheel coupling at all. A suspension link should preferably be coupled to a vehicle body with a sufficient support rigidity to prevent noise or a vibration based on a load input to the vehicle body through the suspension link or to prevent the suspension link from projecting into a passenger's room upon collision. Therefore, when the rear suspension comprises a suspension link whose vehicle body coupling end is located near the rear wheel house panel and which extends in the longitudinal dierction of the vehicle body, the vehicle body coupling end of this suspension link should be coupled to the vehicle body to obtain a sufficient support rigidity. The present invention has been made in consideration of the above situation, and has as its object to provide a vehicle rear suspension mounting structure in which a vehicle body coupling end of a suspension link extending substantially in a longitudinal direction of a vehicle body is coupled to the vehicle body near a rear wheel house panel to obtain a sufficient support rigidity. According to the invention, this object is obtained by the characterizing features of claim 1. Further, advantageous embodiments are characterized in dependent claims 2 - 7. According to the present invention, since a vehicle body coupling end of a suspension link extending in the longitudinal direction of a vehicle body is supported by a link bracket joined to a rear quarter panel, the suspension link can be coupled to a portion near the rear quarter panel (rear wheel house panel) with a sufficiently high support rigidity. In addition, since this link is disposed to be inclined laterally outwardly toward the forward direction of the vehicle body, noise and a vibration and forward projection of the link upon collision can be prevented. Furthermore, even when the link accidentally projects forward, it can be prevented from projecting into a passenger's room. In the claimed rear suspension mounting structure the rear wheel house portion of a vehicle is constituted by the rear wheel house panel consisting of a rear wheel house inner portion and a rear quarter panel. The rear quarter panel is given with a relatively high rigidity since its thickness is increased because a seat belt retractor is normally attached thereto. The rear quarter panel forms a closed section together with a rear fender. In addition, a belt reinforcement is disposed in the closed section formed by the rear quarter panel and the rear fender. For these reasons, the rear quarter panel has a high mechanical strength and rigidity. In the vehicle rear suspension mounting structure, since a link bracket for supporting a vehicle body coupling end of the suspension link is joined to the rear quarter panel having the high mechanical strength and rigidity, the suspension link is coupled to the rear quarter panel (rear wheel house panel). Other features and advantages of the present invention will be apparent from the following description taken in conjunction with the accompanying drawings, in which like reference characters designate the same or similar parts throughout the figures thereof. BRIEF DESCRIPTION OF THE DRAWINGS Figs. 1 and 2 are a partially cutaway perspective view and a perspective view respectively showing a vehicle and a rear suspension to which an embodiment of the present invention is to be applied; Fig. 3 is a perspective view showing an arrangement of the first embodiment of a rear suspension mounting structure according to the present invention; Fig. 4 is a perspective view showing a link bracket structure shown in Fig. 3; Fig. 5 is a plan view showing a link bracket mounting state when viewed from a direction of an arrow V in Fig. 3; Fig. 6 is a sectional view of a link bracket mounting state taken along a line VI - VI in Fig. 3; Fig. 7 is a perspective view showing the second embodiment; Fig. 8 is a perspective view of a link bracket shown in Fig. 7; Fig. 9 is a sectional view taken along a line IX - IX in Fig. 7; Fig. 10 is a perspective view showing the third embodiment; Fig. 11 is a perspective view showing a link reinforcement shown in Fig. 10; Fig. 12 is a perspective view showing a link bracket shown in Fig. 10; and Figs. 13 and 14 are sectional views taken along lines XIII - XIII and XIV - XIV in Fig. 10, respectively. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Three embodiments of a rear suspension mounting structure according to the present invention will be described below with reference to the accompanying drawings. Fig. 1 is a partially cutaway perspective view showing an arrangement of a vehicle to which an embodiment of a rear suspension mounting structure according to the present invention to be described below is to be applied, and Fig. 2 is a perspective view showing an arrangement of a rear suspension to which the embodiment of the rear suspension mounting structure according to the present invention to be described below is applied. As shown in Fig. 2, a rear suspension 10 is constituted as a multi-link type suspension, and is arranged on a rear wheel house portion 14 of a vehicle 12, more specifically, the rear wheel house portion 14 for a rear right wheel RR, as shown in Fig. 1. The suspension 10 comprises a plurality of suspension links, as shown in Fig. 2. The suspension links include upper and lower longitudinal links 16 and 18, extending substantially in a longitudinal direction of a vehicle body, for mainly supporting a load in the longitudinal direction of the vehicle body (load input from the vehicle wheel), and upper and lower lateral links 20 and 22, extending substantially in a lateral direction of the vehicle body, for mainly supporting a load in the lateral direction of the vehicle body (load input from the vehicle wheel). The suspension 10 is also equipped with a strut 28 consisting of a shock absorber 24 and a spring 26 in addition to the plurality of suspension links 16, 18, 20, and 22. One-end portions of the suspension links 16, 18, 20, and 22 are coupled to a vehicle wheel support member 30 for rotatably supporting the rear right wheel RR, and their other-end portions are rotatably coupled to a vehicle body B. More specifically, the outer ends of the upper and lower lateral links 20 and 22 are coupled to the vehicle wheel support member 30, and their inner ends are coupled to a suspension member 32 constituting a portion of the vehicle body B. The rear end of the upper longitudinal link 16 is coupled to the vehicle wheel support member 30, and its front end is coupled to the vehicle body B in the following manner. The rear end of the lower longitudinal link 18 is coupled to the vehicle wheel support member 30 via the lower lateral link 22, and its front end is coupled to the vehicle body B in an appropriate manner as above. Note that the lower end of the strut 28 is coupled to the vehicle wheel support member 30 via the lower lateral link 22 and its upper end is coupled to a suspension tower upper portion 34 (to be described later) constituting a portion of the vehicle body B. The mounting structure of a vehicle body coupling end (front end) 16a of the upper longitudinal link 16 to the vehicle body is the characteristic feature of the present invention, and various embodiments of the mounting structure will be explained below. First Embodiment Fig. 3 is a perspective view showing the arrangement of the first embodiment of the rear suspension mounting structure, Fig. 4 is a perspective view showing the arrangement of a link bracket shown in Fig. 3, Fig. 5 is a plan view of the upper longitudinal link 16 when viewed from a direction of an arrow V in Fig. 3, and Fig. 6 is a sectional view of the upper longitudinal link mounting state taken along a line VI - VI in Fig. 3. The structure of the rear wheel house portion 14 as a structure of the vehicle body B to which the rear suspension 10 for the rear right wheel RR is attached will be described below. As shown in Fig. 3, the rear wheel house portion 14 is constituted by a rear wheel house panel comprising a rear wheel house inner portion 36, and a rear quarter panel 38 to which the outer side end of the rear wheel house inner portion 36 in the lateral direction of the vehicle body is joined, as shown in Fig. 6. The lower end of the rear wheel house inner portion 36 is joined to the outer side end of a rear floor 40 in the lateral direction of the vehicle body. The upper and lower ends of the rear quarter panel 38 are joined to a rear fender 42 located outside the panel 38 in the lateral direction of the vehicle body. The rear quarter panel 38 and the rear fender 42 form a closed space 44 which is closed with respect to an external portion. A belt reinforcement 46 is disposed in the closed space 44 to improve a rigidity of the vehicle body B. As shown in Fig. 6, the upper end of the belt reinforcement 46 is clamped between the upper ends of the rear quarter panel 38 and the rear fender 42, and these three ends are integrated by welding, and its lower end is welded to a middle portion of the rear quarter panel 38. A suspension tower lower portion 48 is integrally formed on the central upper portion of the rear wheel house inner portion 36. The above-mentioned suspension tower upper portion 34 is integrally mounted on the upper end of the suspension tower lower portion 48. The suspension tower upper and lower portions 34 and 48 constitute a suspension tower section. As described above, the upper longitudinal link 16 extending substantially in the longitudinal direction of the vehicle body is disposed to extend laterally outwardly toward the forward direction of the vehicle body, as shown in Fig. 3, and to be inclined downward toward the forward direction of the vehicle body although not shown. The vehicle body coupling end 16a of the upper longitudinal link 16 is welded to a cylindrical sleeve 52 storing a rubber bushing 52a therein. The vehicle body coupling end 16a is pivotally supported on a link bracket 50 via a support bolt 54 which extends through the rubber bushing 52a. The support bolt 54 is fixed to the link bracket 50 by a nut 56. The link bracket 50 is fixed over the rear wheel house inner portion 36 and the rear quarter panel 38 via two mounting bolts 58 and nuts 60, as will be described in detail below. As shown in Fig. 4, the link bracket 50 comprises a main body 50a constituted by three segments 50a 1 , 50a 2 , and 50a 3 , which are connected to define a U shape when viewed from the top, and flange portions 50b and 50c integrally extending outwardly from the upper edges of the opposing segments 50a 1 and 50a 3 of the main body 50a. Through holes 50d and 50e through which the support bolt 54 described above extends are formed in the two segments 50a 1 and 50a 3 , respectively. Mounting holes 50f and 50g through which the mounting bolts 58 are inserted are formed in the flange portions 50b and 50c, respectively. One flange portion 50b located inward in the lateral direction of the vehicle body is fixed to the lower surface of the rear wheel house inner portion 36 via the set of the mounting bolt 58 and the nut 60. The other flange portion 50c located outward is fixed to the lower surface of the rear quarter panel 38 via the set of the mounting bolt 58 and the nut 60. A seat belt retractor (not shown) is attached to the rear quarter panel 38. Since the seat belt retractor is attached, the thickness of the rear quarter panel 38 is relatively large to give a predetermined mechanical strength and a predetermined rigidity. The rear quarter panel 38 forms the closed space 44 together with the rear fender 42, as shown in Fig. 6. Furthermore, the belt reinforcement 46 is disposed in the closed space 44. In this manner, the rear quarter panel 38 can have a sufficiently high mechanical strength and rigidity. In the first embodiment, one end of the link bracket 50 is joined to the rear quarter panel 38 having the high mechanical strength and rigidity. Therefore, a support rigidity of the vehicle body coupling end 16a of the upper longitudinal link 16 by the link bracket is sufficiently high, and, hence, noise or a vibration caused by a load input from the rear right wheel RR through the upper longitudinal link 16 can be suppressed. Even if a large load in a direction of an arrow A in Fig. 5 acts on the upper longitudinal link 16 upon collision, the upper longitudinal link 16 can be prevented from projecting forward into the vehicle body as much as possible since the support rigidity by the link bracket 50 is high. Furthermore, the link bracket 50 for supporting the vehicle body coupling end 16a of the upper longitudinal link 16 is joined to the rear quarter panel 38 located laterally outside the vehicle body with respect to the wheel house inner portion 36. As a result, the upper longitudinal link 16 is inclined laterally outwardly toward the forward direction of the vehicle body, as shown in Fig. 5. In this manner, even if the upper longitudinal link 16 projects forward upon reception of an excessive load upon collision, it projects outside a passenger's room. Therefore, the upper longitudinal link 16 can be prevented from projecting into the passenger's room, thus advantageously assuring a "crash space". Second Embodiment Fig. 7 is a perspective view showing an arrangement of the second embodiment of a rear suspension mounting structure, Fig. 8 is a perspective view of an arrangement of a link bracket shown in Fig. 7, and Fig. 9 is a sectional view of a rear suspension mounting state taken along a line IX - IX in Fig. 7. In the second embodiment, a rear wheel house portion 14 of a vehicle body, a structure near it, the extending direction of an upper longitudinal link 16, and the like are the same as those in the first embodiment. Thus, the same reference numerals denote the same parts and a detailed description thereof will be omitted. The same applies to the third to fifth embodiments to be described later. In the second embodiment, a vehicle body coupling end 16a of the upper longitudinal link 16 is coupled and supported on a link bracket 62 having a structure different from that in the first embodiment via a rubber bushing by a mounting bolt 54 and a nut 56. The link bracket 62 is constituted by a pair of parallel support segments 62a and 62b spaced apart by a predetermined distance, and a coupling segment 62c for coupling the upper ends of the two support segments 62a and 62b so as to define a U shape when viewed from the front side. A pair of through holes 62d and 62e through which the mounting bolt 54 described above is inserted are formed in the support segments 62a and 62b. A bulge portion 64 whose upper end portion is bulged upward in a box-like shape is formed on a portion of the rear wheel house inner portion 36, which portion is located immediately before a suspension tower section. The bulged portion 64 and a rear quarter panel 38 define a recess portion 66 with an open lower surface. A belt reinforcement 46 is bent at its middle portion toward the rear quarter panel 38 in a closed space 44. The lower portion of the belt reinforcement 46 is in contact with and welded to the rear quarter panel 38. In the recess portion 66, the link bracket 62 is disposed from below. Through holes 64a and 38a through which the mounting bolt 54 is inserted are formed in a portion of the left side wall of the bulged portion 64 which defines the left side surface of the recess portion 66, and a portion of the rear quarter panel 38 which defines the left side surface, where the link bracket 54 is disposed. Furthermore, as the characteristic feature of the second embodiment, the belt reinforcement 46 extends vertically downward to a position immediately aside the position of the link bracket 62. A through hole 46a is also formed in the belt reinforcement 46 to be matched with the through hole 38a formed in the rear quarter panel 38. More specifically, the mounting bolt 54 extends through the through hole 64a formed in the bulged portion 64 of the rear wheel house inner portion 36, and the through hole 62d formed in the inner support segment 62a of the link bracket 62 in the widthwise direction of the vehicle body, then extends through the rubber busing 52a, the through hole 62e formed in the outer support segment 62b of the link bracket 62 in the widthwise direction of the vehicle body, the through hole 38a formed in the rear quarter panel 38, and the through hole 46a formed in the belt reinforcement 46a in turn, and is commonly fastened by the nut 56. In the second embodiment, the link bracket 62 to which the vehicle body coupling end 16a of the upper longitudinal link 16 is coupled is joined to the rear quarter panel 38. As a result, the same effect as in the first embodiment can be obtained. In addition, in the second embodiment, since the belt reinforcement 46 is joined to a portion where the link bracket 62 is joined, the support rigidity by the link bracket 62 can be further improved. Third Embodiment Fig. 10 is a perspective view showing an arrangement of the third embodiment of a rear suspension mounting structure, Fig. 11 is a perspective view showing a link reinforcement structure shown in Fig. 10, Fig. 12 is a perspective view showing an arrangement of a link bracket shown in Fig. 10, and Figs. 13 and 14 are sectional views of the rear suspension mounting state taken along lines XIII - XIII and XIV - XIV in Fig. 10, respectively. In the third embodiment, a vehicle body coupling end 16a of an upper longitudinal link 16 is supported by a link bracket 62 which is the same as that in the second embodiment via a rubber bushing 52a by a mounting bolt 54 and a nut 56. A belt reinforcement 46 is disposed in a closed space 44, as in the second embodiment. Furthermore, as the characteristic feature of the third embodiment, a link reinforcement 68 is disposed in the closed space 44. The link reinforcement 68 comprises a U-shaped main body 68a when viewed from the top, as shown in Fig. 11. Joint tongue portions 68b integrally extend from the respective edges of the main body 68a. As shown in Figs. 10 and 13, the link reinforcement 68 extends substantially in the vertical direction in the closed space, and is joined to the bent portion and the lower surface of the belt reinforcement 46 and the outer side surface and the upper surface of a rear quarter panel 38 via the corresponding tongue portions 68b. As shown in Figs. 13 and 14, a coupling segment 62c of the link bracket 62 is welded to a portion of the rear quarter panel 38, where the lower end portion of the link reinforcement 68 is joined. In Fig. 14, positions indicated by alternate long and short dashed lines indicate positions of the lower edge of the belt reinforcement 46, and the lower edge of a rear fender (not shown). In the third embodiment, since the link bracket 62 is joined (welded) to the rear quarter panel 38, the same effect as in the first embodiment can be obtained. In the third embodiment, since the link reinforcement 68 is joined (welded) to a portion of the rear quarter panel 38 where the link bracket 62 is joined, the link bracket 62 can provide a higher support rigidity.

Claims: A vehicle rear suspension mounting structure comprising an upper suspension link (16) and a lower suspension link (18) and being mounted to a vehicle body (B), the other end of a rear suspension (10) having said upper suspension link (16), one end of which is coupled to a wheel support member (30) rotatably supporting a vehicle wheel (RR), said suspension link (16) extending substantially in a longitudinal direction of said vehicle body, and comprising a vehicle body coupling end (16a) formed on the other end thereof; a link bracket (50, 62) supporting said vehicle body coupling end (16a); and joint means (60) joining said link bracket (50, 62) to a rear quarter panel (38) constituting an upper portion of a rear wheel house portion (14), said rear wheel house portion (14) further comprising a rear wheel inner portion (36) which is joined to said rear quarter panel (38) at an inner end thereof in a widthwise direction of said vehicle body (B); characterized in that said rear quarter panel (38) and a rear fender (42) of the vehicle body (B) form a closed space (44) having at least one reinforcement member (46, 68) to provide a direct rigid support by the rear quarter panel (38) for said upper suspension link (16) from the vehicle body (B). The mounting structure according to claim 1, wherein said link bracket (50, 62) is joined so that it straddles between said rear quarter panel (38) and said rear wheel inner portion (36) by means of said joint means (60). The mounting structure according to claim 1 or 2, wherein said rear wheel house inner portion (36) comprises a bulged portion (64) which is bulged upward in a rectangular shape an a joint portion to said rear quarter panel (38), and a lower surface of which defines a recess portion (66) with an open lower surface, said link bracket (62) being fitted in said recess portion (66) from the below, and being joined to be commonly fastened together with said rear wheel house inner portion (36) and said rear quarter panel (38) via a bolt (54). The mounting structure according to a preceding claim, wherein said rear fender (42) is joined to an outer portion of said rear quarter panel (38), and said reinforcement member is a belt reinforcmenet (46), a lower end of said belt reinforcement (46) extending to a portion of said rear quarter panel (38) where said link bracket (62) is joined, and being fixed to said portion of said rear quarter panel (38). The mounting-structure according to claim 4, wherein the lower end of said belt reinforcement (46) is commonly fastened to said link bracket (62) via a bolt (54). The mounting structure according to claim 1 or 2, wherein said link bracket (62) is welded to a lower surface of said rear quarter panel (38). The mounting structure according to claim 6, further comprising: a link reinforcement (68) for coupling said belt reinforcement (46) and an upper surface of a portion of said rear quarter panel (38) where said link bracket (62) is joined, and reinforcing a mechanical strength of said rear quarter panel (38) of said portion where said link bracket (62) is joined.

Inventors: FUJINAKA MITSURU, IIDA EIICHIRO, KOMATSU NOBUHIRO, KONDO TOSHIRO, SATO MOTOHARU, FUJINAKA, MITSURU, IIDA, EIICHIRO, KOMATSU, NOBUHIRO, KONDO, TOSHIRO, SATO, MOTOHARU
Applicants: MAZDA MOTOR, MAZDA MOTOR CORPORATION
Application year: 1990
Main classification: B60G7
IPC codes: B60G7, B62D25, B60G3