JP2005178556A - Vehicular front part structure - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce yaw inertial moment generated when a vehicle turns and to improve operation stability by installing a power train as backward as possible in a vehicular front structure equipped with a steering unit mounted to a cross member at a plurality of positions through bush members. <P>SOLUTION: When the steering unit 9 comprising a steering mechanism is installed to the cross member 5 in a power unit 8, especially between a transmission 7 and the steering unit 9, the installation at a part close to the transmission 7 is carried out by an embedded bush member 17 to avoid an interference of the bush member and the power train. The installation of the steering unit 9 other than the embedded bush member 17 is carried out by an exterior type bush member 20. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a structure in which a steering unit is attached to a cross member via a bush member in a front structure of a vehicle, and particularly relates to a technique for improving the structure of mounting by a bush member.

  Conventionally, for example, in Patent Document 1 below, a power unit including an engine and a transmission is arranged in an engine room at the front portion of a vehicle, and the power unit extends in the front-rear direction of the vehicle on the vehicle rear side. A cross member (corresponding to subframe 17 in Patent Document 1) extending in the vehicle width direction is fixed by the side frame (corresponding to front side members 23 and 25 in Patent Document 1). It has been. A steering unit (corresponding to the steering rack 11 in Patent Document 1) having a vehicle steering mechanism is attached to the cross member via an insulator having anti-vibration performance.

JP 05-32169 A

By the way, in a vehicle, there exists a request | requirement of wanting to arrange | position the power train which is a heavy article as much as possible to the vehicle back side, ie, the vehicle center side in the vehicle front-back direction. This is because the yaw moment of inertia generated when the vehicle turns can be reduced by arranging the power train on the rear side, thereby improving the operability.
On the other hand, when the steering unit is attached to the cross member, the vibrations of the engine and the vehicle body are transmitted to the steering in the vehicle interior, so that the steering performance of the occupant is prevented from deteriorating. A plurality of parts close to each other are connected to each other through a relatively large bush member for reducing vibration transmission. In this case, the steering unit arranges and connects at least one bush member to a corresponding portion of the cross member at the front of the vehicle relative to the steering unit, and another bush member from the steering unit to the rear of the vehicle. It arrange | positions and it connects with the site | part corresponding to this corresponding to the cross member, and, thereby, the steering unit is supported reliably.
However, if the large bush member is connected in this way, a large bush member is disposed between the steering unit and the power train on the front side of the steering unit. If you try to position the power train on the rear side, the bushing member and the power train interfere with each other, and the power train cannot be placed on the rear side as much as possible, which reduces the yaw moment of inertia as much as possible. It was not.

  The present invention has been made in view of the above-described problems, and an object of the present invention is to be close to the power unit in the front structure of a vehicle in which the steering unit is attached to the cross member and a plurality of parts via bush members. By making the bush member to be embedded into an embedded bush member embedded in the cross member, the power train is installed on the rear side as much as possible to improve the operability. In addition, the bushing members other than the embedded bushing member are externally attached bushing members that are not embedded in the crossmember, so that the embedded bushing member prevents the position accuracy of the steering unit from being lowered relative to the crossmember. Thus, it is to ensure high positional accuracy.

In order to achieve such an object, in the invention according to claim 1 of the present invention, in the front part of the vehicle, a predetermined cross member that is positioned rearward of the power unit and extends in the vehicle width direction; A front portion of a vehicle comprising a vehicle steering mechanism and comprising a steering unit that is disposed substantially in parallel with the cross member and is attached to a plurality of positions via bushing members that reduce vibrations, respectively. In the structure, of the plurality of bush members, the bush member adjacent to the power unit between the steering unit and the power unit is embedded in advance so as to be embedded in a predetermined amount from the outer shape of the cross member. The bush member other than the embedded bush member is the bush member. Characterized in that it is a external bushing member disposed so as not embedded in the cross member.
According to such a configuration, the bush member close to the power unit among the plurality of bush members for attaching the steering unit to the cross member so as to be capable of vibration isolation is embedded in the embedded bush member embedded in the cross member. By doing so, the powertrain can be installed as far back as possible. Thereby, the yaw moment of inertia generated when the vehicle turns can be reduced, and the operability can be improved.
Further, when the embedded bush member is installed on the cross member, a relatively large diameter hole is formed, and the embedded bush member is installed there. It cannot be made constant but varies individually, and the degree of variation also increases. This leads to a great deterioration in the position accuracy of the steering unit with respect to the cross member. When the position accuracy deteriorates in this way, in a vehicle that requires a large number of parts to be mounted compactly in a narrow space, for example, the steering unit and adjacent parts interfere with each other due to vibration during traveling, and abnormal noise is generated. There are problems such as the occurrence of damage and the damage of parts and the like.
Therefore, in the present invention according to the configuration of the first aspect, the external bushing member that is not embedded in the cross member other than the embedded bushing member among the plurality of bushing members is further provided. A high positional accuracy is realized by the bush member, whereby the overall positional accuracy of the steering unit with respect to the cross member can be maintained at a high accuracy, and the generation of abnormal noise and the damage of parts and the like can be prevented.

According to a second aspect of the present invention, in the first aspect, the degree of displacement between the steering unit and the cross member in the embedded bush member is determined by the steering unit and the cross member in the external bush member. It is characterized by being configured to be larger than the degree of displacement between.
According to such a configuration, by increasing the degree of displacement between the steering unit and the cross member in the embedded bush member, it is possible to improve the assembling property when the steering unit is assembled to the cross member.
In other words, the position accuracy of the embedded bush member with respect to the cross member is not relatively good, but the positional accuracy is inferior by increasing the degree of displacement of the embedded bush member, which is slightly inferior in accuracy. Even so, it can be easily assembled using a large degree of displacement.

According to a third aspect of the present invention, in the first aspect, the embedded bush member is positioned so that the power train is positioned above the embedded bush member in the vertical direction when viewed from the vehicle width direction. It is characterized by being arranged and inclined with respect to the upper part of the embedded bush member so that the lower part is directed obliquely downward.
With such a configuration, the interference between the embedded bush member and the power train can be avoided as much as possible, the power unit can be positioned further rearward, and the operability can be improved.

As described above, in the invention according to the present invention, of the plurality of bush members for attaching the steering unit to the cross member in a vibration-proof manner, the bush member adjacent to the power unit is embedded in the cross member. By using the type bush member, the power train can be installed on the rear side as much as possible. Thereby, the yaw moment of inertia generated when the vehicle turns can be reduced, and the operability can be improved.
In the present invention, except for the embedded bush member, an external bush member that is not embedded in the cross member is used, so that high positional accuracy can be realized by the external bush member. As a result, the position accuracy of the steering unit relative to the cross member can be maintained with high accuracy as a whole, thus preventing abnormal noise caused by interference between the steering unit and the adjacent components, and damage to the components due to the interference. it can.

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

(First embodiment)
The vehicle according to the first embodiment is a front engine / front drive (FF) type vehicle, and a front frame (Fig. (Not shown) is provided, and a subframe 1 shown in FIG. 1 is arranged below the front frame. A plurality of suspension arms (not shown) are connected to the subframe 1, and a support member (not shown) that rotatably supports the front wheels is connected to the suspension arms. (Not shown) can be suspended. The subframe 1 is supported on the front frame via mounts 2, 2, 3, 3 and the like.
The subframe 1 has side frames 4 and 4 extending in the vehicle longitudinal direction on the left and right sides in the vehicle width direction, and a cross member 5 extending in the vehicle width direction and connecting and fixing the side frames 4 and 4. It consists of and.
A powertrain unit 8 including an engine 6 and a transmission 7 and connected and supported by, for example, a front frame is positioned in front of the cross member 5 and obliquely above. The engine 6 is a so-called horizontal type in which the crankshaft (not shown) is arranged in the vehicle width direction. Accordingly, the engine 6 is adjacent to the engine 6 in the vehicle width direction. The transmission 7 is located. In particular, in the present embodiment, if the left side in FIG. 1 is defined as the left side when the vehicle is viewed from the front, the engine 6 is laid out on the left side and the transmission 7 is laid out on the right side.

Further, a steering unit 9 having a steering mechanism for performing a steering operation of the vehicle is installed above the cross member 5, and the steering unit 9 is arranged at the left and right ends of the vehicle toward the cross member 5. It is being fixed to cross member 5 via bracket 10a ... 10d extended in the direction.
A steering gear mechanism portion 11 is provided at the left end portion of the steering unit 9, and a steering shaft 12 extends from the steering gear mechanism portion 11 toward the rear side of the vehicle and obliquely upward. The rear end of the shaft extends to the vicinity of the driver's seat in the passenger compartment, and a steering (not shown) is attached.
Although not shown, a steering nack extends along the longitudinal direction inside the steering unit 9, and a gear is provided in the vicinity of the steering gear mechanism 11 of the steering nack along the longitudinal direction of the steering nack. The gear is formed and meshed with a pinion gear connected to the steering shaft 12 in the steering gear mechanism 11, thereby forming a general rack-and-pinion steering mechanism.

Tie rods 13 are respectively provided at both ends of the steering knuckle in the vehicle width direction, and support members for supporting the wheels are connected to the vehicle outer side end portions of the tie rods 13 via knuckle arms (not shown). A general configuration is formed.
With such a steering unit 9 and its peripheral configuration, when the vehicle occupant steers the steering, the steering nack is displaced to the left and right in the vehicle width direction, and accordingly, the wheels are steered and the vehicle turns. I will run.

FIG. 2 is a schematic view showing the AA cross section of FIG. 1, and a transmission 7 is arranged in front of the vehicle from the steering unit 9. A bracket 10a is fixed to the steering unit 9, but the cross member 5 side of the bracket 10a extends obliquely downward on the front side of the vehicle, and its tip end portion 14 is formed in a plate shape. At the same time, a bolt hole 15 extending in the vertical direction is formed in the tip portion 14.
On the other hand, in the cross member 5, a hole 16 is formed in a portion corresponding to the tip portion 14 of the upper surface panel 5 a of the cross member 5, and a cylindrical embedded bush member 17 is inserted into the hole 16 in the cross member 5. It is installed so as to be embedded almost entirely in the member 5.
The embedded bush member 17 includes a rubber bush 17b in which a bolt hole 17a is formed along a cylindrical central axis, and a sleeve that covers the cylindrical surface of the rubber bush 17b and is fixed to the rubber bush 17b in a fitted state. It is comprised from the shape-shaped support part 17c. An upper portion of the support portion 17c is formed with a flange 17d extending in the outer diameter direction over the outer peripheral side of the cylindrical shape. The flange 17d is fixed to the outer peripheral portion of the hole 16 so as to be buried. The push-in bush member 17 is fixed to the cross member 5.

The bolt 18a is passed through the bolt hole 15 of the bracket 10a and the bolt hole 17a of the rubber bush 17b, and the tip of the bolt 18a is fastened to the nut 18b on the lower side of the embedded bush member 17, thereby steering. The unit 9 is supported by the cross member 5. At this time, disc-like spacers 18c and 18c are provided between the tip portion 14 and the head portion of the bolt 18a and between the embedded bush member 17 and the nut 18b, respectively. Further, a rubber bush 17b is interposed between the flange portion 17d and the tip portion 14, and between the spacer 18c on the nut 18b side and the support portion 17c.
As a result, all the vibration of the cross member 5 is transmitted to the steering unit 9 via the rubber bush 17b, thereby reducing the vibration to the steering.

  In addition, the lower portion of the transmission 7 is positioned on the vehicle front side from the bolt 18a. A plurality of disk-shaped gears (not shown) are arranged inside the transmission 7 so that the orthogonal axis of the disk is the vehicle. Since they are arranged side by side so as to be substantially parallel to the width direction, generally, when the transmission 7 is viewed from the vehicle width direction, the outer diameter on the rear side and the lower side is along the outer periphery of the disk-shaped gear. Thus, the front side is formed so as to fall obliquely downward. Therefore, by making the bush member 17 embedded, the mounting parts such as the bolts 18a and the embedded bush member 17 can be lowered and positioned so as to avoid interference with the transmission 7. The entire power unit 8 including the machine 7 can be located on the vehicle rear side.

FIG. 3 is a schematic view showing a BB cross section of FIG. 1, and a bracket 10b is extended from the vehicle right side portion of the steering unit 9 toward the vehicle direction side. An external bushing member 20 is formed. This externally attached bush member 20 has a cylindrical rubber bush 20b fitted into the inner periphery of a vertically extending hole 20a formed at the tip of the bracket 10b so that its central axis is in the vertical direction. A bolt hole 20c is formed along the central axis of the rubber bush 20b.
A thickness D1 of the rubber bush 20b in the radial direction of the cylindrical shape is located immediately behind the transmission 7 shown in FIG. 2, and is an embedded bush installed on the front side of the vehicle with respect to the steering unit 9. It is set smaller than the similar thickness D2 of the rubber bush 17b of the member 17.
Further, a bolt hole 21 is formed in the rear portion of the cross member 5, whereby the bolt 22 is passed through the bolt hole 20 c of the rubber bush 20 b and the tip thereof is a screw (not shown) on the inner periphery of the bolt hole 21. The steering unit 9 is supported on the cross member 5 via the rubber bush 21 by being fastened along the groove. A rubber bush 20b is interposed between the bracket 10b and the bolt 22 and between the bracket 10b and the surface of the cross member 5.
As a result, the vibration of the steering unit 9 can be prevented in the same manner as the embedded bush member 17.

  A mounting structure to the cross member 5 by a bracket 10c extending from the left side portion of the steering unit 9 toward the rear of the vehicle and a bracket 10d extending from the left side portion of the steering unit 9 toward the front of the vehicle. These are the same as the mounting structure using the external bushing member 20 shown in FIG.

  As described above, in the present embodiment, when the steering unit 9 is attached to the cross member 5, the power unit 8, particularly between the transmission 7 and the steering unit 9, is attached at a portion close to the transmission 7. By using the embedded bushing member 17, the powertrain 8 can be installed as far back as possible to improve the operability by reducing the yaw moment of inertia.

Further, when the embedded bush member 17 is installed in the cross member 5, the embedded bush member 17 must be installed in the large hole 16 formed in the cross member 5, as in the external bush member 20. Compared with the case where the external bushing member 20 is attached to the small-diameter bolt hole 21 formed in the cross member 5, it is difficult to ensure high positional accuracy. Therefore, the installation position of the embedded bushing member 17 with respect to the cross member 5 cannot always be made constant and varies individually, and the degree of variation thereof also increases.
In the external bushing member 20, the fitting of the rubber bush 20b into the hole 20a can be performed before the steering unit 9 is installed on the cross member 5, and in this case, the positional accuracy of the bolt hole 20c. Can be improved. On the other hand, in the embedded bush member 17, when the rubber bush 17 b is assembled after the support portion 17 c is fixed to the cross member 5, a hard rubber bush is attached to the support portion 17 c which is a part of a large vehicle body structure. 17b must be fitted and assembled, and the positional accuracy of the bolt holes 17a is likely to deteriorate, and even in this case, individual variations become large.
Due to the deterioration of the installation position of the embedded bushing member 17 or the installation position of the bolt hole 17a, the positional accuracy of the steering unit 9 with respect to the cross member 5 is greatly deteriorated. When the positional accuracy deteriorates in this way, in a vehicle that requires a large number of parts to be mounted compactly in a narrow space, for example, the steering unit 9 and the adjacent parts interfere with each other due to vibration during traveling, and thus different. There are problems such as noise and damage to the steering unit 9 and parts.
However, since the bushing members other than the embedded bushing member 17 are the externally attached bushing members 20, the steering unit 9 is made highly accurate with respect to the cross member 5 by such an externally attaching bushing member 20. Therefore, it is possible to prevent occurrence of abnormal noise and damage of parts.

The embedded bush member 17 is a right side portion of the steering unit 9 and is used for attachment to the cross member 5 at a portion close to the transmission 7 between the transmission 7 and the steering unit 9. In particular, an external bushing member 20 is employed for attachment to the cross member 5 on the left side of the steering unit 9 adjacent to the steering gear mechanism 11 and the steering shaft 12. Further, in this case, with respect to the thickness of each rubber bush, the thickness of the rubber bush 20b of the externally attached bush member 20 is set to be thinner than the thickness of the rubber bush 17d of the embedded bush member 17.
As a result, the left side of the steering unit 9 that requires higher positional accuracy with respect to the cross member 5 is provided by the thin rubber bush 20b by providing parts such as the steering shaft 12, and therefore the cross The position accuracy of the left side of the steering unit 9 relative to the member 5 can be improved.

(Second Embodiment)
Next, a second embodiment will be described with reference to FIG.
In the second embodiment, only the arrangement of the embedded bushing member 17 is changed with respect to the first embodiment, and as shown in FIG. An inclined surface 5b that is inclined so as to sink downward is formed at the front side, and the embedded bush member 17 is arranged so that its bolt hole 17a is parallel to an orthogonal axis substantially orthogonal to the inclined surface. It is installed at an angle. As a result, the mounting parts such as the bolts 18a and the embedded bushing member 17 can be further lowered and positioned, and the transmission 7 can be further displaced rearward, thereby reducing the yaw moment of inertia. Improved maneuverability.

(Other embodiments)
In the above-described embodiment, only one embedded bush member 17 is used. However, if it is between the power unit 8 and the steering unit 9, for example, the embedded bush member is attached to the bracket 10d. 17 may be applied.
In the above embodiment, the case where the steering unit 9 is attached to the cross member 5 of the sub-frame 1 has been described. Instead, both ends of the steering unit 9 are fixed to the front frame. In addition, the bush member according to the present invention may be applied to a case where the bush member is attached to a cross member extending in the vehicle width direction.

1 is a schematic plan view of a subframe 1 according to a first embodiment of the present invention. AA schematic sectional drawing of FIG. BB schematic sectional drawing of FIG. The schematic sectional drawing equivalent to FIG. 2 based on the 2nd Embodiment of this invention.

Explanation of symbols

1: Subframe 5: Cross member 7: Transmission 8: Power unit 9: Steering unit 10a,... 10d: Bracket 17: Embedded bush member 20: External bush member

Claims (3)

In the vehicle front portion, a predetermined cross member that is located on the rear side of the power unit and extends in the vehicle width direction,
A front portion of a vehicle comprising a vehicle steering mechanism and comprising a steering unit that is disposed substantially in parallel with the cross member and is attached to a plurality of positions via bushing members that reduce vibrations, respectively. In structure
Of the plurality of bush members, an embedded bush disposed in advance between the steering unit and the power unit so that the bush member adjacent to the power unit is embedded in a predetermined amount from the outer shape of the cross member. A front structure of a vehicle, wherein the bush members other than the embedded bush member are externally mounted bush members arranged so that the bush is not embedded in the cross member.   The degree of displacement between the steering unit and the cross member in the embedded bush member is configured to be greater than the degree of displacement between the steering unit and the cross member in the external bush member. The vehicle front structure according to claim 1. The embedded bush member is disposed so that the power train is positioned on the upper side in the vertical direction from the upper portion of the embedded bush member when viewed from the vehicle width direction, and the upper portion of the embedded bush member is On the other hand, the vehicle front structure according to claim 1, wherein the vehicle front structure is disposed so as to be inclined so that the lower portion is directed obliquely downward.

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