Vehicle frame

Abstract

This provides a vehicle frame that easily increases the mounting space directly below the side rails. [Solution] The vehicle frame comprises a channel-shaped steel first side rail positioned at the front of the vehicle, a channel-shaped steel second side rail positioned behind the first side rail, a connecting rail connecting the first and second side rails, with one end positioned in the groove of the first side rail and the other end positioned in the groove of the second side rail, and stiffeners positioned in the gap between the lower part of the connecting rail and the lower flange in the groove of the first side rail, and in the gap between the lower part of the connecting rail and the lower flange in the groove of the second side rail.

Description

Technical Field

[0001] The present disclosure relates to a vehicle body frame.

Background Art

[0002] Electric vehicles such as electric trucks equipped with batteries have been proposed. The battery is disposed, for example, below the vehicle body frame as shown in Patent Document 1.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, when the battery is mounted directly below the side rail, depending on the shapes of the side rail and the battery, it may not be possible to ensure the minimum ground clearance of the vehicle. As a countermeasure, assuming that the battery is disposed directly below the side rail, there is also a method of widening the space between the side rail and the road surface by partially shortening the width of the side rail in the height direction. However, since the side rail has a special shape, there is a risk of high mold costs when the side rail is integrally formed.

[0005] The present disclosure has been made in view of the above problems, and an object thereof is to provide a vehicle body frame that easily expands the mounting space directly below the side rail.

Means for Solving the Problems

[0006] The present disclosure has been made to solve at least a part of the above problems, and can be realized as the following aspects or application examples.

[0007] The vehicle frame according to this application example comprises a channel-shaped steel first side rail positioned on the front of the vehicle, a channel-shaped steel second side rail positioned behind the first side rail, a connecting rail having one end positioned in the groove of the first side rail and the other end positioned in the groove of the second side rail to connect the first and second side rails, and stiffeners positioned in the gap between the lower part of the connecting rail and the lower flange in the groove of the first side rail, and in the gap between the lower part of the connecting rail and the lower flange in the groove of the second side rail.

[0008] According to this application example, multiple side rails, such as those obtained by dividing a conventional side rail into front and rear sections, are connected by a connecting rail with a shorter width in the vehicle height direction. This allows for the expansion of the mounting space for components directly below the connecting rail. Therefore, the mounting space directly below the side rails can be easily increased without using side rails of a special shape. [Brief explanation of the drawing]

[0009] [Figure 1] Plan view of the vehicle body. [Figure 2] This is an enlarged perspective view of the vehicle frame. [Figure 3] This is a left side view of the vehicle frame. [Figure 4] This is a cross-sectional view of the vehicle frame 2 along line IV-IV in Figure 1. [Modes for carrying out the invention]

[0010] Embodiments of this disclosure will be described below with reference to the drawings. Figure 1 is a plan view of a part of the vehicle body 1. In the following description, the longitudinal direction of the vehicle body 1 is defined as the vehicle length direction X, the front wheels 31 of the vehicle body 1 are at the front, and the opposite side is at the rear. The left-right direction as viewed from the rear of the vehicle body 1 is defined as the vehicle width direction Y, and the up-down direction of the vehicle body 1 is defined as the vehicle height direction Z.

[0011] The vehicle configured with the vehicle body 1 of this embodiment is an electric vehicle that uses the electricity stored in the battery 41 as driving force. Examples of electric vehicles include electric vehicles (EVs), hybrid electric vehicles (HEVs), plug-in hybrid vehicles (PHVs), or fuel cell vehicles (FCVs).

[0012] In this embodiment, the vehicle equipped with the body 1 is assumed to be an electric truck. The body frame 2 is a ladder frame chassis frame applicable to large vehicles such as trucks. The body frame 2 has a pair of left and right side rails 21 (21L, 21R) and a plurality of cross members 22, etc.

[0013] The side rail 21L located on the left side of the vehicle body 1 and the side rail 21R located on the right side extend in the vehicle length direction X. The pair of side rails 21 are arranged parallel to each other and spaced apart on the left and right sides.

[0014] The cross member 22 extends in the vehicle width direction Y and connects the left side rail 21L and the right side rail 21R.

[0015] The vehicle frame 2 supports various components of the vehicle. The vehicle frame 2 houses, for example, a transmission mechanism (not shown) that transmits the steering force of the steering wheel to the front wheels 31 via a steering shaft, a battery 41, a control unit 42, and a drive unit 43. The front wheels 31 are driven wheels suspended from the vehicle frame 2.

[0016] Battery 41 is a secondary battery used to drive the vehicle. Battery 41 is a high-voltage battery module, such as a lithium-ion battery or a nickel-metal hydride battery. Battery 41 is composed of multiple battery packs housed in a battery case. Battery 41 is electrically connected to at least the drive unit 43 via the control unit 42.

[0017] Further, the battery 41 is supported so as to be suspended from the left and right side rails 21 via a support member (not shown). This support member is fixed to one or more of the connecting rail 73, the first side rail 71, the second side rail 72, and the cross member 22.

[0018] The control unit 42 controls and monitors the operations of various components of the vehicle. The control unit 42 is, for example, an ECU (Electronic Control Unit) that functions as a computer, a PDU (Power Distribution Unit) that functions as a power distributor, and the like. The control unit 42 has a function of monitoring the state of the battery 41, for example. Further, the control unit 42 controls so as to appropriately distribute the power of the battery 41 to each power supply destination.

[0019] The drive unit 43 includes an inverter 431, an electric motor 432, a gearbox 433, a differential device 434, etc., and is integrally configured.

[0020] The inverter 431 is electrically connected to the electric motor 432. The electric motor 432 is mechanically connected to the gearbox 433. Further, the gearbox 433 is mechanically connected to the differential device 434.

[0021] The inverter 431 converts the DC power input from the battery 41 side into AC power of a predetermined frequency and supplies it to the electric motor 432. The electric motor 432 converts the power input from the inverter 431 into driving force (torque) and transmits it to the gearbox 433.

[0022] The gearbox 433 is a speed reduction mechanism having a plurality of gears, converts the torque input from the electric motor 432 side at a predetermined gear ratio, and outputs it to the differential device 434 side. The differential device 434 distributes the driving force input from the gearbox 433 side to each of the left and right drive shafts 52.

[0023] The drive shaft 52 on the right side of the vehicle body 1 mechanically connects the drive unit 43 and the right rear wheel 51. The drive shaft 52 on the left side mechanically connects the drive unit 43 and the left rear wheel 51. Therefore, the rear wheels 51 function as drive wheels.

[0024] Here, the detailed configuration of the side rail 21 will be described. As shown in the plan view of FIG. 1, the side rail 21 includes a channel-shaped first side rail 71 disposed on the front side of the vehicle, a channel-shaped second side rail 72 disposed on the rear side of the first side rail 71, and a connecting rail 73 that connects the first side rail 71 and the second side rail 72. The first side rail 71, the second side rail 72, and the connecting rail 73 are formed linearly in the front-rear direction in plan view.

[0025] FIG. 2 is an enlarged perspective view of the left side rail 21(21L) of the vehicle body frame 2 as viewed from the rear (in the direction of A in FIG. 1) inside (right side) of the vehicle body frame 2. FIG. 3 is a left side view of the left side rail 21L. FIG. 4 is a cross-sectional view taken along the line IV-IV of the vehicle body frame 2 in FIG. 1.

[0026] In this embodiment, mainly, the configuration around the connection portion of the left side rail 21L(21) of the vehicle body frame 2 and the cross member 22 will be described. However, since the connection portion of the right side rail 21R(21) and the cross member 22 is also formed substantially symmetrically left and right, the same components will be denoted by the same reference numerals and the description thereof will be omitted or simplified.

[0027] As shown in FIG. 3, the rear end 71b of the first side rail 71 on the side of the second side rail 72 is inclined forward from the upper part to the lower part. Also, the width of the second side rail 72 in the vehicle height direction Z is formed to be substantially the same as that of the first side rail 71. The front end 72a of the second side rail 72 on the side of the first side rail 71 is also inclined rearward from the upper part to the lower part.

[0028] As shown in the III-III cross-sectional view of Figure 3, the connecting rail 73 is formed as a channel-shaped steel opening on the inside of the vehicle frame 2. The front end 73a and rear end 73b of the connecting rail 73 are inclined to narrow from top to bottom in the longitudinal direction (vehicle length direction X) of the connecting rail 73. Therefore, the connecting rail 73 is formed in a roughly trapezoidal shape when viewed from the side.

[0029] Furthermore, the connecting rail 73 is formed to be shorter than the vertical width (width in the vehicle height direction Z) of the first side rail 71 and the second side rail 72. One end 731 of the connecting rail 73 is positioned in the groove 71S of the first side rail 71, and the other end 732 is positioned in the groove 72S of the second side rail 72. Thus, the first side rail 71 and the second side rail 72 are connected by the connecting rail 73 while spaced apart in the vehicle length direction X.

[0030] The first side rail 71 and the connecting rail 73 are connected in the vehicle width direction Y by fastening their bottoms 713 and 733 together with a connecting member 76, which will be described later, using multiple fasteners S (see the III-III cross-sectional view in Figure 3). The second side rail 72 and the connecting rail 73 are also connected in the vehicle width direction Y by fastening their bottoms 723 and 733 together with multiple fasteners S.

[0031] The side rail 21 is further equipped with a stiffener 74. The stiffener 74 is positioned to fill the gap between the lower part of the connecting rail 73 and the lower flange 714 of the groove 71S of the first side rail 71, and the gap between the lower part of the connecting rail 73 and the lower flange 724 of the groove of the second side rail 72.

[0032] The stiffener 74 is formed to be shorter in the vehicle height direction Z than the connecting rail 73 and is formed in the shape of a channel steel opening to the inside of the vehicle frame 2. The front end 74a and rear end 74b of the stiffener 74 are inclined to narrow in the longitudinal direction (vehicle length direction X) of the stiffener 74 from top to bottom. Therefore, the stiffener 74 is formed in a roughly trapezoidal shape when viewed from the side.

[0033] As shown in Figure 4, the stiffener 74 positioned in the groove 71S of the first side rail 71 is positioned so that its front end 74a aligns linearly with the front end 73a of the connecting rail 73, and its rear end 74b aligns linearly with the rear end 71b of the first side rail 71. Similarly, the stiffener 74 positioned in the groove 72S of the second side rail 72 is positioned so that its front end 74a aligns linearly with the front end 72a of the second side rail 72, and its rear end 74b aligns linearly with the rear end 73b of the connecting rail 73.

[0034] The stiffeners 74 provided on the first side rail 71 and the stiffeners 74 provided on the second side rail 72 are connected in the vehicle height direction Z by fastening the upper flange 741 of each stiffener 74 to the lower flange 734 of the connecting rail 73 with a plurality of fasteners S.

[0035] As shown in Figure 2, the cross member 22 comprises a cross member body 75 formed in the shape of a channel steel opening on the rear side of the vehicle body frame 2, and connecting members 76 attached to the left and right ends of the cross member body 75.

[0036] The connecting member 76 is formed in the shape of a short channel steel, and each flange 761 of the connecting member 76 is positioned to sandwich the flange 751 of the cross member body 75 from the outside. The connecting member 76 and the cross member body 75 are fixed together by fastening the flanges 751 and 761 to each other with fasteners S.

[0037] The bottom portion 762 of the connecting member 76 is fastened together with the bottom portion 733 of the connecting rail 73 and the bottom portion 713 of the cross member 22 by fasteners S. This connects the cross member 22 and the side rail 21.

[0038] Although Figure 2 shows the connection structure between the first side rail 71, the connecting rail 73, and the cross member 22, the connection structure between the second side rail 72, which is positioned behind the first side rail 71, the connecting rail 73, and the cross member 22 is also formed in a substantially symmetrical manner. However, the cross member body 75 positioned on the second side rail 72 is also arranged in a channel-shaped steel form that opens to the rear.

[0039] The above describes the configuration of the vehicle body frame 2 of this embodiment, which comprises a channel-shaped steel first side rail 71 positioned on the front side of the vehicle, a channel-shaped steel second side rail 72 positioned behind the first side rail 71, a connecting rail 73 connecting the first side rail 71 and the second side rail 72, and stiffeners 74 positioned in the gap between the lower part of the connecting rail 73 and the lower flanges 714 and 724 of the grooves 71S and 72S of the first side rail 71 or the second side rail 72, respectively.

[0040] By connecting multiple side rails 71 and 72, which are similar to conventional side rails divided into front and rear sections, with a connecting rail that is shorter in width in the vehicle height direction, the mounting space SP for components such as batteries 41 can be expanded directly below the connecting rail 73. Therefore, the mounting space SP directly below the side rails can be easily increased to ensure the minimum ground clearance h (see Figure 4) without using side rails of a special shape.

[0041] Furthermore, since the ends (front ends 73a, 74a and rear ends 73b, 74b) of the connecting rail 73 and stiffener 74, which are positioned within the first side rail 71 or the second side rail 72, are formed to be inclined, the load on the first side rail 71 and the second side rail 72 at the same position in the vehicle length direction X, received from the ends of the connecting rail 73 and stiffener 74, can be reduced.

[0042] Furthermore, since the stiffener 74 is fixed to the connecting rail 73 and not directly fixed to the first side rail 71 or the second side rail 72, the bending load or torsional load from the connecting rail 73 is transmitted to the first side rail 71 or the second side rail 72 via the stiffener 74, thereby preventing it from concentrating on the side rails 71, 72, and the connecting rail 73.

[0043] This concludes the description of this embodiment. However, the specific configuration shown in this embodiment is merely an example, and the embodiments of the present invention are not limited to the configuration shown in this embodiment.

[0044] For example, in this embodiment, we have described an example in which two first side rails 71 (a side rail that is wider in the front vehicle height direction) and a second side rail 72 (a side rail that is wider in the rear vehicle height direction) are connected by a short connecting rail 73 in the vehicle height direction Z, thereby increasing the mounting space SP directly below the connecting rail 73, in one location. However, the configuration in which the mounting space SP is provided by the first side rail 71, the second side rail 72, and the connecting rail 73 may be provided in two or more locations on the front and rear of the side rail 21. [Explanation of symbols]

[0045] 1. Vehicle body 2. Vehicle frame 21 (21L, 21R) Side Rails 22 Crossmember 31 Front Wheel 41 batteries 42 Control Unit 43 Drive Unit 51 Rear wheel 52 Drive shaft 71 First side rail 72 Second side rail 71S,72S In the groove 72a,73a,74a Front end 71b,73b,74b Rear end 73 Connecting rails 74 Stifna 75 Cross member body 76 Connecting Member 431 Inverter 432 Electric motor 433 Gearbox 434 Differential device 713,723,733,762 bottom 714,724 Lower flange 731,732 One end 734,741,751,761 flange S1~S3 Fasteners SP mounting space X Vehicle length direction Y (vehicle width direction) Z (Vehicle Height Direction) h Minimum ground clearance

Claims

[Claim 1] The first side rail is a channel-shaped steel rail positioned at the front of the vehicle, A channel-shaped steel second side rail is positioned behind the first side rail, A connecting rail having one end positioned in the groove of the first side rail and the other end positioned in the groove of the second side rail, connecting the first side rail and the second side rail, Stiffeners are positioned in the gap between the lower part of the connecting rail and the lower flange in the groove of the first side rail, and in the gap between the lower part of the connecting rail and the lower flange in the groove of the second side rail, A vehicle frame equipped with these features.

Images