Mounting structure of power unit

Abstract

To solve the problem in which a stroke amount of a power unit is not sufficient in conventional mounting structures at the time of a vehicle collision.SOLUTION: A mounting structure of a power unit is given in which a power unit P is fixed to a suspension member 4 while the power unit, a motor 1 and a transmission 3 are horizontally arranged in a right-and-left direction of a vehicle; right and left side brackets Bs, Bs are arranged at an upper part in one side and the other side in the right-and-left direction of the vehicle to fix the motor 1 and the transmission 3; a front bracket Bf to fix a front part of the motor 1 is arranged at a lower part; and a rear bracket Br to fix a rear part of the transmission 3 is arranged. The mounting structure of the power unit balances a vibration proof support function of the power unit P with a function of torque roll receiver and secures a stroke amount of the power unit P at the time of collision of the vehicle.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a power unit mounting structure used to mount a power unit, which serves as a drive source, in a vehicle. [Background technology]

[0002] An example of a conventional power unit mounting structure is described in Patent Document 1. Patent Document 1 describes a transversely mounted engine type power unit including an engine and a transmission, and describes a structure in which the power unit is supported in a vibration-proof manner on the vehicle body via engine mounts arranged at four points on the front, rear, left and right sides of the vehicle. In this mounting structure, the mass of the power unit is supported at three points on the front side, rear side and engine side, and receives torque roll reaction force and the like at one point on the transmission side. As a result, the above mounting structure realizes a reduction in the size of the engine mount on one side in the left-right direction in a limited space. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 5815602 Summary of the Invention [Problem to be solved by the invention]

[0004] In recent years, power units that integrate a motor and a transmission have become common. In the mounting structure of such power units, the importance of receiving torque roll reaction force has increased with the weight reduction of the power unit and the increase in the speed of the motor. Moreover, when the behavior of the power unit in the event of a vehicle collision is taken into consideration, there is a risk that the stroke amount of the power unit will be insufficient in the conventional mounting structure.

[0005] The present invention has been made in consideration of the above-mentioned conventional situation, and aims to provide a power unit mounting structure that integrates a motor and a transmission, which realizes both the vibration-proof support function and the torque crawl support function of the power unit, and can sufficiently ensure the stroke amount of the power unit in the event of a vehicle collision. [Means for solving the problem]

[0006] The mounting structure for a power unit according to the present invention is a mounting structure for mounting a power unit, which is an integrated unit of a motor, an inverter, and a transmission, on a vehicle. In this mounting structure, the power unit has the motor and the transmission arranged side by side in the left-right direction of the vehicle and fixed to a suspension member. The mounting structure is characterized in that it includes, at an upper part, one side bracket for fixing a side of the motor to the suspension member on one side in the left-right direction of the vehicle and the other side bracket for fixing a side of the transmission to the suspension member on the other side in the left-right direction of the vehicle, a front bracket for fixing a front part of the motor to the suspension member on a lower part, and a rear bracket for fixing a rear part of the transmission to the suspension member.

[0007] The above-mentioned power unit mounting structure fixes the power unit to the suspension member at four points, the front, rear, left and right, using side brackets on the left and right sides of the vehicle, and front and rear brackets on the front and rear of the vehicle, so that it receives the vibrations and torque roll reaction force of the power unit.In the event of a vehicle collision, the power unit moves toward the rear of the vehicle while tilting and rotating forward around the fixed point provided by the front bracket. Effect of the Invention

[0008] By adopting the above-mentioned configuration, the power unit mounting structure of the present invention, in a power unit mounting structure integrating a motor and transmission, achieves both the vibration-proof support function of the power unit and the torque crawl support function, and can sufficiently ensure the stroke amount of the power unit in the event of a vehicle collision. [Brief description of the drawings]

[0009] [Figure 1] 1 is a plan view showing a first embodiment of a mounting structure according to the present invention; [Diagram 2] FIG. 2 is a side view of the mounting structure shown in FIG. [Diagram 3] 3 is a side view showing the behavior of the power unit shown in FIG. 2 during a collision. [Figure 4] FIG. 11 is a plan view showing a second embodiment of a mounting structure according to the present invention. [Diagram 5] 5 is a side view showing the behavior of the power unit shown in FIG. 4 during a collision. [Figure 6] FIG. 11 is a side view diagrammatically showing a third embodiment of a mounting structure according to the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] First Embodiment 1 to 3 are diagrams for explaining a first embodiment of a power unit mounting structure according to the present invention. In Fig. 1 and Fig. 2, the left direction is the vehicle front direction, the up-down direction in Fig. 1 is the vehicle left-right direction, and the up-down direction in Fig. 2 is the vehicle up-down direction, and the vehicle is not shown.

[0011] The power unit mounting structure supports a power unit P in a motor room of an electric vehicle. The power unit P in this embodiment is an integrated unit of a motor 1, an inverter 2, and a transmission 3. In this power unit P, the motor 1 and the transmission 3 are arranged side by side in the left-right direction of the vehicle, and the inverter 2 is arranged above the motor 1 and fixed to a suspension member 4.

[0012] In the illustrated example, the power unit P has the motor 1 disposed on the right side of the vehicle, and the transmission 3 disposed on the left side of the vehicle. The motor 1 is disposed so that the axial direction of the output shaft 1A, shown by the dotted line in Fig. 2, is oriented in the left-right direction of the vehicle. The transmission 3 houses a gear mechanism for transmitting power, and is longer than the motor 1 in the front-rear direction of the vehicle.

[0013] The suspension member 4 is a well-known structural member of a vehicle, and has a pair of left and right side frames 4A, 4A extending in the front-rear direction of the vehicle, and a front frame 4B and a rear frame 4C extending in the left-right direction of the vehicle, as shown in Fig. 1. Note that the illustrated suspension member 4 does not include strut housings and the like that suspend the wheel suspension.

[0014] The mounting structure has, at its upper part, one side bracket Bs that fixes the side of the motor 1 to the side frame 4A of the suspension member 4 on one side (right side) in the left-right direction of the vehicle, and the other side bracket Bs that fixes the side of the transmission 3 to the side frame 4A of the suspension member 4 on the other side (left side) in the left-right direction of the vehicle.

[0015] The mounting structure also has a front bracket Bf at its lower part for fixing the front part of the motor 1 to the front frame 4B of the suspension member 4, and a rear bracket Br for fixing the rear part of the transmission 3 to the rear frame 4C of the suspension member 4.

[0016] Here, the suspension member 4 has base portions Qs, Qs, Qf, Qr for fixing the brackets Bs, Bs, Bf, Br, respectively. In addition to the shape of the suspension member 4 itself, the base portions Qs, Qs, Qf, Qr allow the horizontal and vertical arrangement relationships to be set. In this embodiment, for convenience of explanation, the centers of the fixing portions of the brackets Bs, Bs, Bf, Br and the base portions Qs, Qs, Qf, Qr are set as the fixing points Fs, Fs, Ff, Fr, respectively.

[0017] In a more preferred embodiment of the above mounting structure, as shown in Fig. 2, the respective fixing points Fs, Fs of the suspension member 4 of one and the other side brackets Bs, Bs are arranged to align with the position of the center of gravity G in the vehicle fore-and-aft direction of the transmission 3. Fig. 2 shows the relationship between a vertical center line C1 passing through the center of the output shaft 1A of the motor 1, a vertical center line C2 passing through the fixing point Fs of the side bracket Bs, and the position of the center of gravity G in the vehicle fore-and-aft direction of the transmission 3.

[0018] As described above, the mounting structure has the side brackets Bs, Bs disposed relatively higher and the front bracket Bf disposed relatively lower. More precisely, the mounting structure has the fixing point Ff of the front bracket Bf on the suspension member 4 disposed lower than the fixing points Fs, Fs of both side brackets Bs, Bs.

[0019] Furthermore, in a more preferred embodiment of the mounting structure, the front bracket Bf and the rear bracket Br have a rigidity lower than the rigidity of the one and the other side brackets Bs, Bs.

[0020] The power unit mounting structure having the above configuration supports the mass of the power unit P at four points (front, rear, left and right) on the suspension member 4, thereby reducing the load per point compared to a structure that supports the mass at three points. And, by supporting the power unit P at four points, the above mounting structure receives the vibration and torque roll reaction force of the power unit P.

[0021] In addition, since the motor 1 of the power unit P is the seismic source in the above mounting structure, the vibration isolation is improved by fixing the axial side of the output shaft 1A with one side bracket Bs. The front bracket Bf and rear bracket Br are disposed in front of the motor 1 and at the rear of the transmission 3, respectively, and in this case, each of them can be positioned in the left-right direction of the vehicle taking into consideration the center of gravity balance, etc.

[0022] Furthermore, in the case of a vehicle collision, the power unit P moves toward the rear of the vehicle while tilting forward and rotating around the fixed point Ff of the front bracket Bf, as shown in Fig. 2. The amount of this movement toward the rear of the vehicle is the stroke amount of the power unit P during a collision. In this case, in the case of the mounting structure, the amount of movement toward the rear of the vehicle is larger by the amount of the power unit P tilting forward compared to when the power unit P simply moves toward the rear of the vehicle, and the load on the cabin can be reduced or avoided.

[0023] In this way, the above mounting structure, in a mounting structure for a power unit P integrating a motor 1 and a transmission 3, achieves both the vibration-proof support function and the torque crawl support function of the power unit P, and can sufficiently secure the stroke amount of the power unit P in the event of a vehicle collision.

[0024] In addition, in the above mounting structure, the fixing points Fs, Fs of the one and other side brackets Bs, Bs are arranged to match the center of gravity G of the transmission 3 in the vehicle longitudinal direction, so that in the event of a vehicle collision, a radiator or the like at the front of the vehicle interferes with the front part of the motor 1, making it easier to rotate in the pitch direction around the fixing points Fs, Fs of the left and right side brackets Bs, Bs. This makes it possible to rotate the power unit P, which is long in the vehicle longitudinal direction, forward inclination by the transmission 3, and a sufficient stroke amount can be ensured. Note that, when there are multiple fixing points of each bracket on the suspension member 4, the intermediate points may be used instead, or the positioning may be performed taking into consideration variations, etc.

[0025] Furthermore, in the above mounting structure, the fixed point Ff of the front bracket Bf is positioned lower than the fixed points Fs, Fs of the left and right side brackets Bs, Bs. Therefore, in the event of a vehicle collision, the radiator at the front of the vehicle will interfere with the front part of the motor 1, and the power unit P will tend to rotate forward in the pitch direction with the fixed point Ff of the front bracket Bf as the fulcrum, thereby contributing to ensuring a sufficient amount of stroke.

[0026] Furthermore, in the above mounting structure, the front bracket Bf and rear bracket Br have lower rigidity than the left and right side brackets Bs, Bs, so that in the event of a vehicle collision, the front and rear brackets Bf, Br deform or break before the side brackets Bs, Bs, making it easier for the power unit P to rotate forward in the pitch direction with the fixed points Fs, Fs of the side brackets Bs, Bs as fulcrums, which can contribute to ensuring a sufficient amount of stroke.

[0027] 4 to 6 are diagrams showing second and third embodiments of the power unit mounting structure according to the present invention. In the following embodiments, the same components as those in the first embodiment are given the same reference numerals, and detailed description thereof will be omitted.

[0028] <Second embodiment> The power unit mounting structure shown in FIG. 4 is structured such that, in a side view, a distance A from a fixed point Fs of the side bracket Bs on the suspension member 4 to a fixed point Ff of the front bracket Bf on the suspension member 4 is longer than a distance B from the fixed point Fs of the side bracket Bs to a fixed point Fr of the rear bracket Br (A>B).

[0029] The mounting structure having the above configuration can obtain the same effects as the first embodiment, and in particular, in the event of a vehicle collision, a moment acts on the rear bracket Br, making it more likely to break, and the power unit P can more easily tilt forward and rotate in the pitch direction with the fixed point Fs of the left and right side brackets Bs as a fulcrum, as shown in Fig. 5, ensuring a sufficient stroke amount. Note that, if the fixed points Fs, Fs of the left and right side brackets Bs, Bs are asymmetric and different, it is sufficient to consider the average length of each.

[0030] <Third embodiment> The power unit mounting structure, the main part of which is shown in Fig. 6, has an inverter 2 disposed on top of a motor 1, and has a notch 2A at the upper corner of the rear end of the vehicle in a side view. The notch 2A forms an inclined surface with a downward slope toward the rear of the vehicle.

[0031] In a vehicle equipped with a power unit P including a motor 1, a high-rigidity master cylinder 10 that constitutes a braking system is generally disposed above and behind the motor 1. In the event of a vehicle collision, the power unit P tilts forward and rotates while moving toward the rear of the vehicle, which may cause interference with the master cylinder 10.

[0032] Therefore, in the above mounting structure, by adopting the above configuration, it is possible to obtain the same effect as in the first embodiment, and in the event of a vehicle collision, when the power unit P moves toward the rear of the vehicle while tilting forward from the state shown by the solid line in Figure 6 as shown by the virtual line in the same figure, the master cylinder 10 comes into sliding contact with the cutout portion 2A of the inverter 2, thereby avoiding excessive load on the high-voltage inverter 2.

[0033] The details of the configuration of the power unit mounting structure according to the present invention are not limited to the above-described embodiments, but can be modified as appropriate without departing from the gist of the invention, and it is also possible to combine the configurations of the above-described embodiments. [Explanation of symbols]

[0034] 1 Motor 1A output shaft 2 Inverter 2A Notch 3. Gearbox 4 Suspension members Bf Front bracket Br Rear bracket Bs Side bracket Ff Front bracket fixing point on suspension member Rear bracket fixing point on Fr suspension member Fs Fixed point of side bracket on suspension member G. Transmission center of gravity in the vehicle's longitudinal direction P Power Unit

Claims

1. A mounting structure for mounting a power unit in which a motor, an inverter, and a transmission are integrated on a vehicle, the power unit has the motor and the transmission arranged side by side in the left-right direction of the vehicle and fixed to a suspension member, a side bracket for fixing a side portion of the motor to the suspension member on one side in the left-right direction of the vehicle, and a side bracket for fixing a side portion of the transmission to the suspension member on the other side in the left-right direction of the vehicle, A power unit mounting structure comprising a front bracket at a lower portion for fixing a front portion of the motor to the suspension member, and a rear bracket for fixing a rear portion of the transmission to the suspension member.

2. 2. A power unit mounting structure according to claim 1, wherein the respective fixing points of the one and the other side brackets on the suspension member are positioned in accordance with the center of gravity position of the transmission in the vehicle longitudinal direction.

3. 3. The power unit mounting structure according to claim 2, wherein a fixing point of said front bracket on said suspension member is disposed lower than fixing points of said one and the other side brackets.

4. 4. The power unit mounting structure according to claim 1, wherein the front bracket and the rear bracket have a rigidity lower than a rigidity of the one and the other side brackets.

5. 4. A power unit mounting structure as claimed in any one of claims 1 to 3, characterized in that, in a side view, a distance from a fixing point of the side bracket on the suspension member to a fixing point of the front bracket on the suspension member is longer than a distance from a fixing point of the side bracket on the suspension member to a fixing point of the rear bracket on the suspension member.

6. 4. The power unit mounting structure according to claim 1, wherein the inverter is disposed above the motor and has a notch at an upper corner of the rear end of the vehicle.

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