JP4985242B2 - Drive unit support structure - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a support structure for a drive unit which can suppress an increase in weight to enhance the rigidity of a stay member. <P>SOLUTION: The support structure for the drive unit comprises a rear drive unit 6 for transmitting a rotary input from a drive source 1 arranged at the front side of a vehicle to rear drive wheels 9, a rear propeller shaft 7 for connecting the drive source 1 to a rear drive unit 6, and a stay member 10 for supporting the rear drive unit 6 to the vehicle body. The stay member 10 has a thick part 10C1 at a compressed support part side subjected to compression by the torque reaction of the rear propeller shaft 7 and has a thin part 10D1 at a tension support part side subjected to tension by a torque reaction with an increase in weight suppressed, and the rigidity of the stay member 10 enhanced. <P>COPYRIGHT: (C)2009,JPO&amp;INPIT

Description

  The present invention relates to a drive unit support structure, and more particularly, to a stay member structure that supports a drive unit on a vehicle body.

  For example, the vehicle drive mechanism is separated into a front drive unit having an engine and arranged in front of the vehicle, and a rear drive unit having a transmission and a rear differential device, and the front drive unit and the rear drive unit are connected to the propeller. There has been proposed a vehicle connected to a shaft so that power can be transmitted (for example, described in Patent Document 1).

In the vehicle described in Patent Document 1, the rear side of the rear drive unit is elastically supported on the vehicle body by the subframe, and the front side is supported by a stay member straddling the tunnel portion of the rear cross member on the left and right.
Japanese Patent Laid-Open No. 2005-162198

  However, in the technique described in Patent Document 1, in order to support the torque reaction force of the rear drive unit, increasing the rigidity by increasing the thickness of the stay member uniformly to the left and right results in an increase in weight.

  Therefore, an object of the present invention is to provide a drive unit support structure capable of suppressing the increase in weight and increasing the rigidity of the stay member.

  In the drive unit support structure of the present invention, the stay member on the side of the compression support portion that receives compression by the torque reaction force of the rear propeller shaft is the thick portion, and the stay member on the side of the tension support portion that receives the tension is the thin portion.

  According to the support structure of the drive unit of the present invention, the stay member is made thicker at the compression side support part, which is higher in load than the tension side support part, and thinner at the tension side support part, which is lower in load than the compression side support part. As a result, the increase in weight can be suppressed and the rigidity of the stay member can be increased.

  Hereinafter, specific embodiments to which the present invention is applied will be described in detail with reference to the drawings.

“First Embodiment”
FIG. 1 is a schematic configuration diagram showing the vehicle of the first embodiment, FIG. 2 is a perspective view of a main part when a portion supporting the rear drive unit of the vehicle of the first embodiment is viewed from above the vehicle, and FIG. 3 is the first embodiment. FIG. 4 is a cross-sectional view taken along the line AA in FIG. 2, and FIG. 5 is a stay member for the vehicle according to the first embodiment. FIG. 6 is a view in which the rotational reaction force by the front propeller shaft and the rear propeller shaft acts on the stay member in the vehicle of the first embodiment.

  The vehicle according to the first embodiment has a structure in which an engine is arranged in front of the vehicle and a transmission is arranged in the rear of the vehicle, and is a 4WD vehicle that is driven by all wheels (four wheels). As shown in FIG. 1, a drive source 1 that is an engine and a front drive unit 3 that transmits rotational input from the drive source 1 to front drive wheels (front wheels) 2 are arranged in front of the vehicle. Yes. On the other hand, a rear drive unit 6 including a rear differential device 4 and a transmission 5 disposed immediately before the rear differential device 4 is disposed at the rear of the vehicle.

  In this vehicle, a rear propeller shaft 7 that connects the drive source 1 and the rear drive unit 6 so as to extend from the front of the vehicle toward the rear of the vehicle is provided at the center of the vehicle. Further, in this vehicle, a front propeller shaft 8 that connects the rear drive unit 6 and the front drive unit 3 is provided so as to extend from the rear of the vehicle toward the front of the vehicle substantially parallel to the rear propeller shaft 7.

  The rear propeller shaft 7 is a component that transmits power from the front drive unit 3 to the rear drive unit 6. The front propeller shaft 8 is a component that transmits power from the rear drive unit 6 disposed at the rear of the vehicle to the front drive wheels 2.

  In the 4WD vehicle configured as described above, the rotational force from the drive source 1 is transmitted to the rear drive unit 6 via the rear propeller shaft 7, and the rear drive wheel (rear wheel) 9 is rotated by the rear drive unit 6. . On the other hand, the rotational force by the drive source 1 is transmitted from the rear drive unit 6 to the front drive unit 3 via the front propeller shaft 8, and the front drive wheel 2 is rotated by the front drive unit 3. Thereby, in the vehicle of the first embodiment, all the wheels of the front drive wheel 2 and the rear drive wheel 9 are rotationally driven.

  In the first embodiment, as shown in FIGS. 2 to 4, the rear drive unit 6 has a front portion supported by the vehicle body 11 by the stay member 10 and a rear portion supported by the rear suspension frame 12. . The stay member 10 is formed as a rigid support member made of an aluminum cast product extending in the vehicle width direction, and both end portions 10A in the longitudinal direction are fixed to the vehicle body front-rear skeleton member (sill) 13, and the middle in the longitudinal direction. The portion 10B is fixed to the left and right skeleton member (cross member) 14. The stay member 10 is fixed to the vehicle body 11 by normal fastening means using bolts and nuts.

  The stay member 10 is formed with a pair of support portions 10C and 10D that support the rear drive unit 6 with the rear propeller shaft 7 interposed therebetween. A mount member 15 is attached to each of the support portions 10C and 10D, and the rear drive unit 6 is fixed to the stay member 10 by fixing the mission mount bracket 16 fixed to the transmission member 5 to the mount member 15 with fastening means. Has been. As shown in FIG. 5, the stay member 10 is provided with ribs 17 for maintaining rigidity and reducing weight. A plurality of ribs 17 are formed at appropriate intervals in the vehicle width direction inside the stay member 10 having a substantially inverted U-shaped cross section that opens downward. The rib 17 has a plate shape extending in the vehicle vertical direction so as to withstand the torque reaction force of the rear propeller shaft 7 and the front propeller shaft 8.

  As shown in FIG. 6, when the rear propeller shaft 7 and the front propeller shaft 8 are rotated in the direction indicated by the arrow A, the stay member 10 has a torque reaction force F in a direction opposite to the rotation direction of the propeller shafts. Works. Therefore, the compressive force F <b> 1 due to the torque reaction force F acts on one support portion 10 </ b> C supporting the rear drive unit 6. A tensile force F2 due to the torque reaction force F acts on the other support portion 10D.

  Thus, the opposing compressive force F1 and tensile force F2 act on the two support portions 10C and 10D of the stay member 10. Therefore, in the first embodiment, the stay member 10 is efficiently formed in such a manner that rigidity is given to a portion that requires rigidity and rigidity is not given to a portion that does not require that much rigidity. That is, the rigidity of the stay member 10 is ensured and the weight is reduced.

  Specifically, the stay member 10 on the compression support portion side that is compressed by the torque reaction force F of the rear propeller shaft 7 is a thick portion 10C1, and the stay member 10 on the tension support portion side is a thin portion 10D1. The thick portion 10C1 has a thickness of the stay member 10 that is thicker than other portions, and the one support portion 10C that has sufficient rigidity to withstand the compression force F1 is thick. The thin-walled portion 10D1 is thinned by forming the first cutout portion 18 by cutting out the lower portion of the stay member 10, and sufficient rigidity is ensured even when the tensile force F2 is applied. Yes.

  Further, the portion between the thick portion 10C1 and the thin portion 10D1 of the stay member 10 does not act on the compressive force F1 or the tensile force F2, and therefore the second notch portion 19 which is a recess in which the front propeller shaft 8 is disposed. Has been. The second notch 19 is formed by notching the upper side of the stay member 10, and the front propeller shaft 8 is disposed in the notched recess.

  In the first cutout portion 18 formed below the thin portion 10D1 of the stay member 10 configured in this manner, a floor lower component 20 extending in the vehicle front-rear direction is disposed. Here, the lower floor component 20 is an exhaust tube for discharging exhaust gas and exhaust sound discharged from the drive source 1. A front propeller shaft 8 is disposed in a second cutout portion 19 formed between the thick portion 10C1 formed in the stay member 10 and the first cutout portion 18. From another point of view, the front propeller shaft 8 is disposed between the rear propeller shaft 7 and the thick portion 10C1 that are disposed substantially at the center of the left and right sides of the upper side of the stay member 10.

  As described above, according to the first embodiment, the stay member 10 on the compression support portion side that receives compression by the torque reaction force F of the rear propeller shaft 7 is the thick portion 10C1, and the tension support portion side that receives tension is on the side. By making the stay member 10 the thin portion 10D1, it is possible to increase the rigidity of the stay member 10 while suppressing an increase in weight. In short, it is possible to secure the rigidity of the necessary portion while suppressing an increase in weight by making the portion requiring rigidity thick and making the portion not requiring rigidity thin.

  Further, according to the first embodiment, the lower floor component 20 (exhaust tube or the like) can be disposed in the first cutout portion 18 in which the lower side of the stay member 10 is cut out. The lower surface height of can be increased. Therefore, according to the first embodiment, the minimum ground clearance can be increased, and contact between the lower floor component 20 and the ground can be suppressed.

  Normally, considering the rigidity of the stay member 10, it is preferable to pass the stay member 10 having a uniform thickness in the vehicle width direction of the vehicle, but the lower floor is restricted by the floor height and the lower is the lowest ground. High and regulated. Since the lower floor part (exhaust tube) 20, the front propeller shaft 8, the rear propeller shaft 7, various harnesses, piping and the like must be passed through the narrow space, the stay member 10 cannot be passed straight in the vehicle width direction. Therefore, as in the first embodiment, the minimum ground height of the vehicle is achieved by providing an efficient structure in which the thickness of the stay member 10 is given to a necessary portion and not given to an unnecessary portion. Can be increased, and contact between the lower floor component 20 and the ground can be suppressed.

  In addition, according to the first embodiment, the rear propeller shaft 7 is arranged at the substantially left and right center on the upper side of the stay member 10, and the second cut formed between the rear propeller shaft 7 and the thick portion 10C1 of the stay member 10 is formed. Since the front propeller shaft 8 is disposed in the notch portion 19, the center of gravity of the rear drive unit 6 is closer to the front propeller shaft 8. As a result, a load is applied to the front propeller shaft 8 side of the rear drive unit 6 as compared with the opposite side, but the stay member 10 is thick and has a thick wall portion 10C1, which suppresses an increase in weight. The rear drive unit 6 can be supported efficiently.

In addition, according to the first embodiment, since the floor lower part 20 (exhaust tube or the like) is arranged in the first cutout part 18 in which the lower side of the stay member 10 is cut out, the lower surface height of the floor lower part 20 is increased. Can be high. Further, according to the first embodiment, in addition to this, the front propeller shaft 8 is disposed in the second cutout portion 19 in which the other upper side of the stay member 10 is cut out, so that the upper surface height of the front propeller shaft 8 is increased. Can be lowered, and the floor can be lowered (room 2 can be enlarged).
Further, according to the first embodiment, since the stay member 10 is fixed to the left and right skeleton member 14, the mounting rigidity can be improved and the side impact load can be absorbed by the stay member 10.

  Further, according to the first embodiment, since the stay member 10 is fixed to the vehicle body front-rear skeleton member 13, the mounting rigidity is further improved and the side impact load can be absorbed by the stay member 10.

  Further, according to the first embodiment, the stay member 10 is formed with the ribs 17 extending in the vehicle vertical direction, so that the rigidity can be maintained and the weight can be reduced.

“Second Embodiment”
FIG. 7 is a schematic configuration diagram showing the vehicle of the second embodiment, and FIG. 8 is a diagram in which the rotational reaction force by the rear propeller shaft acts on the stay member in the vehicle of the second embodiment.

  The vehicle according to the second embodiment is not a 4WD vehicle as in the first embodiment, but is an FR vehicle that drives a rear drive wheel with a structure in which an engine is arranged in front of the vehicle and a transmission is arranged in the rear of the vehicle. As shown in FIG. 7, a drive source 1 that is an engine and a front drive unit 3 are arranged in front of the vehicle. On the other hand, a rear drive unit 6 including a rear differential device 4 and a transmission 5 disposed immediately before the rear differential device 4 is disposed at the rear of the vehicle.

  In this vehicle, a rear propeller shaft 7 that connects the front drive unit 3 and the rear drive unit 6 so as to extend from the front of the vehicle toward the rear of the vehicle is provided at the center of the vehicle. In addition, since the vehicle of 2nd Embodiment is not a 4WD vehicle like the vehicle of 1st Embodiment, the front propeller shaft 8 is not provided.

  In the FR vehicle configured as described above, the rotational force from the drive source 1 is transmitted from the front drive unit 3 to the rear drive unit 6 via the rear propeller shaft 7, and the rear drive unit 6 causes the rear drive wheels (rear) The wheel 9 is rotated. Since the front drive wheel 2 is an FR vehicle, the rotational force from the drive source 1 is not transmitted.

  Since the stay member 10 of the second embodiment does not use the front propeller shaft 13, as shown in FIG. 8, the stay member 10 of the second embodiment does not have the second notch portion 19 formed in the stay member 10 of the second embodiment. Only the 1st notch part 18 for arrange | positioning the lower floor components 20 is formed. The stay member 10 according to the second embodiment is the same as the stay member 10 according to the first embodiment except that the second notch 19 is not formed.

  According to the second embodiment, as in the first embodiment, the stay member 10 on the compression support portion side that receives compression by the torque reaction force F of the rear propeller shaft 7 is the thick portion 10C1, and the tension support that receives tension. Since the stay member 10 on the portion side is the thin portion 10D1, the rigidity of the stay member 10 can be increased while suppressing an increase in weight.

  Further, according to the second embodiment, the lower floor component 20 (exhaust tube or the like) can be disposed in the first cutout portion 18 in which the lower side of the stay member 10 is cut out. The lower surface height of can be increased. Therefore, according to the second embodiment, the minimum ground clearance can be increased, and contact between the lower floor component 20 and the ground can be suppressed.

  Although specific embodiments to which the present invention is applied have been described above, the above-described embodiments are merely examples of the present invention and are not limited to the above-described embodiments.

FIG. 1 is a schematic configuration diagram showing a vehicle according to the first embodiment. FIG. 2 is a perspective view of a main part when a portion supporting the rear drive unit of the vehicle according to the first embodiment is viewed from above the vehicle. FIG. 3 is a perspective view of main parts when a portion supporting the rear drive unit of the vehicle according to the first embodiment is viewed from below the vehicle. 4 is a cross-sectional view taken along line AA in FIG. FIG. 5 is a cross-sectional view of the stay member of the vehicle according to the first embodiment. FIG. 6 is a diagram in which the rotational reaction force by the front propeller shaft and the rear propeller shaft acts on the stay member in the vehicle of the first embodiment. FIG. 7 is a schematic configuration diagram showing a vehicle according to the second embodiment. FIG. 8 is a diagram in which the rotational reaction force by the rear propeller shaft acts on the stay member in the vehicle of the second embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Drive source 2 ... Front drive wheel 3 ... Front drive unit 4 ... Rear differential device 5 ... Transmission 6 ... Rear drive unit 7 ... Rear propeller shaft 8 ... Front propeller shaft 9 ... Rear drive wheel 10 ... Stay member 11 ... Car body 13 ... Front and rear skeleton members (sil)
14 ... left and right skeleton members (cross members)
17 ... Rib 18 ... First notch 19 ... Second notch 20 ... Floor lower part

Claims (7)

A drive source disposed at the front of the vehicle, a rear drive unit disposed at the rear of the vehicle and transmitting a rotational input from the drive source to a rear wheel;
A rear propeller shaft connecting the drive source and the rear drive unit;
In a drive unit support structure comprising a stay member that supports the rear drive unit on a vehicle body,
The stay member is fixed to a vehicle body, and includes a pair of support portions that support the rear drive unit across the rear propeller shaft.
The stay member on the compression support portion side that receives compression by the torque reaction force of the rear propeller shaft is made a thick portion,
The drive unit support structure, wherein the stay member on the side of the tension support portion that receives tension by the torque reaction force of the rear propeller shaft is a thin portion. The drive unit support structure according to claim 1,
The thin portion on the side of the tension support portion of the stay member is formed by a cutout portion formed by cutting out the lower side of the stay member,
The drive unit support structure, wherein a floor lower part extending in the vehicle front-rear direction is arranged in the notch. A drive unit support structure according to claim 1 or 2,
A front drive unit that transmits rotational input from the drive source to the front wheels;
A front propeller shaft connecting the rear drive unit and the front drive unit,
The rear propeller shaft is arranged at the substantially right and left center above the stay member,
The drive unit support structure, wherein the front propeller shaft is disposed between the rear propeller shaft and the thick portion of the stay member. A drive unit support structure according to claim 1 or 2,
A front drive unit that transmits rotational input from the drive source to the front wheels;
A front propeller shaft connecting the rear drive unit and the front drive unit,
While arranging a lower floor part that extends in the vehicle front-rear direction in a cutout portion formed by cutting out the lower side of either one of the left and right directions of the stay member with respect to the rear propeller shaft,
The drive unit support structure, wherein the front propeller shaft is arranged in a cutout portion formed by cutting out the other upper side of the stay member. A drive unit support structure according to any one of claims 1 to 4,
A drive unit support structure, wherein the stay member is fixed to a left and right skeleton member of a vehicle body. A drive unit support structure according to any one of claims 1 to 5,
A drive unit support structure, wherein the stay member is fixed to a vehicle body longitudinal frame member. A drive unit support structure according to any one of claims 1 to 6,
The stay member includes a rib extending in a vehicle vertical direction.

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