WO2021116650A1

WO2021116650A1 - Mount on inverter housing

Info

Publication number: WO2021116650A1
Application number: PCT/GB2020/052563
Authority: WO
Inventors: Ian Foster; Matthew Kelly; Louis Garner
Original assignee: Dyson Technology Limited
Priority date: 2019-12-13
Filing date: 2020-10-14
Publication date: 2021-06-17
Also published as: GB201918387D0; CN114829176A; GB2590387A; GB2590387B

Abstract

A vehicle (100) includes a vehicle body (101) and an electric drive unit (102, 112). The electric drive unit (102, 112) includes a gearbox (104), an electric machine (106) mounted to the gearbox (104) and configured to provide drive to the gearbox (104), and a drive electronics unit (108) mounted to the gearbox (104) and configured to provide drive current to the electric machine (106). The electric drive unit (102, 112) is mounted to the vehicle body (101) via a plurality of mounts, the plurality of mounts including a drive electronics mount (134) disposed on the drive electronics unit (108) and connecting the electric drive unit (108) to the vehicle body (101).

Description

MOUNT ON INVERTER HOUSING

Field of the Invention

The present invention relates to a vehicle having an electric drive unit.

Background of the Invention

Electric and hybrid electric vehicles are becoming increasingly common. One such electric vehicle may comprise one or more electric drive units (EDUs), each of which may drive a corresponding pair of road wheels. For example, each EDU includes a gearbox, and an electric motor mounted to the gearbox.

Each EDU is mounted to the vehicle, typically by way of one or more mounts attached to the gearbox. It would be desirable to improve the way in which an EDU is mounted to a vehicle.

Summary of the Invention

In accordance with a first aspect of the invention, there is provided a vehicle comprising: a vehicle body; and an electric drive unit, the electric drive unit comprising: a gearbox; an electric machine mounted to the gearbox and configured to provide drive to the gearbox; and a drive electronics unit mounted to the gearbox and configured to provide drive current to the electric machine; wherein the electric drive unit is mounted to the vehicle body via a plurality of mounts, the plurality of mounts including a drive electronics mount disposed on the drive electronics unit and connecting the electric drive unit to the vehicle body. By mounting the electric drive unit to the vehicle body at least partly by way of such a drive electronics mount, a more compact and/or cheaper to manufacture mount may be employed. In at least certain configurations, this arrangement may also allow for reduced loads on the mount compared to, for example, connecting the mount solely to the gearbox. Reduced loads may allow for the use of a less stiff mount, which may improve noise, vibration and harshness (NVH).

The drive electronics mount may be a separate component attached to a housing of the drive electronics unit. This arrangement may allow a more compact and/or cheaper to manufacture mount to be employed and may allow for removal of the mount from the drive electronics unit without removing the drive electronics unit from the gearbox.

The drive electronics mount may comprise part of a housing of the drive electronics unit. This arrangement may reduce the number of parts required to mount the electronics drive unit to the vehicle body.

The drive electronics mount may be attached to the electric drive unit only via the drive electronics unit. This may allow the use of a more compact mount.

The mounts may include an electric machine mount disposed on the electric machine and connecting the electric drive unit to the vehicle. For example, the electric machine mount may be a separate component attached to a housing of the electric machine. This arrangement may allow a more compact and/or cheaper to manufacture mount to be employed and may allow for removal of the mount from the electric machine without removing the electric machine from the gearbox.

The electric machine mount may comprise part of a housing of the electric machine. This arrangement may reduce the number of parts required to mount the electronics drive unit to the vehicle body. The electric machine mount may be attached to the electric drive unit only via the electric machine. This arrangement may allow the use of a more compact mount.

The plurality of mounts may include at least one further mount.

The electric drive unit may be substantially T-shaped in front elevation or plan, wherein the drive electronics unit and electric machine are positioned at opposite ends of a crossbar of the T-shape, and the gearbox forms an upright of the T-shape. This may provide a compact layout offering good mounting characteristics.

The electric drive unit may be configured to drive a pair of rear wheels or front wheels of the vehicle.

The vehicle may comprise a further electric drive unit, the further electric drive unit comprising: a further gearbox; a further electric machine mounted to the further gearbox and configured to provide drive to the further gearbox; and a further drive electronics unit mounted to the further gearbox and configured to provide drive current to the further electric machine; wherein the further electric drive unit is mounted to the vehicle body via a plurality of further mounts, the further mounts including a further drive electronics mount disposed on the further drive electronics unit and connecting the further electric drive unit to the vehicle body.

The electric drive unit may be configured to drive a pair of wheels of the vehicle, and the further electric drive unit may be configured to drive another pair of wheels of the vehicle.

A housing of the drive electronics unit may be the same as a housing of the further drive electronics unit, and the drive electronics mount and the further drive electronics mount may be different to each other. This arrangement may allow for simplified manufacture and stock-management during production.

The drive electronics unit may comprise an inverter.

The at least one further mount of the electric drive unit and/or the further electric drive unit may comprise at least one torque reaction mount that bears substantially none of the electric drive unit’s weight. For example, the at least one further mount may comprise exactly one torque reaction mount.

The electric drive unit and/or the further electric drive unit may be mounted such that its elongate axis is substantially vertical.

The drive electronics mount and the electric machine mount (and/or the further drive electronic mount and the further electric machine mount) may together bear a majority of the electric drive unit’ s weight. For example, the drive electronics mount and the electric machine mount may together bear substantially all of the electric drive unit’s weight (and/or the further drive electronic mount and the further electric machine mount)

The at least one further mount of the electric drive unit and/or the further electric drive unit may comprise at least one weight-bearing mount.

All mounts of the electric drive unit and/or the further electric drive unit may bear a portion of the electric drive unit’s weight.

In order that the present invention may be more readily understood, embodiments of the invention will now be described, by way of example, with reference to the accompanying drawings, in which: Figure 1 is a partially see-through side view of a vehicle comprising a front- mounted electric drive unit (EDU) and a further rear-mounted EDU;

Figure 2 is a partially see-through front view of the vehicle of Figure 1, showing the front-mounted EDU of Figure 1; Figure 3 is a partially see-through rear view of the vehicle of Figure 1, showing the further EDU of Figure 1;

Figure 4 is a left elevation of the front-mounted EDU;

Figure 5 is a right elevation of the front-mounted EDU;

Figure 6 is a perspective view of the front-mounted EDU, with mounts omitted for clarity;

Figure 7 is a further perspective view of the front-mounted EDU;

Figure 8 is a perspective view of the front-mounted EDU showing its attachment to a front subframe of the vehicle;

Figure 9 is a left elevation of a further EDU; Figure 10 is a right elevation of the further EDU of Figure 9;

Figure 11 is a perspective view of the further EDU, with mounts omitted for clarity;

Figure 12 is a further perspective view of the further EDU;

Figure 13 is a plan view of the further EDU; Figure 14 is a plan view of the further EDU, mounted to a rear subframe of the vehicle of Figure 1.

Detailed Description of the Invention Referring to the drawings, a vehicle 100 includes an electric drive unit (EDU) in the form of an EDU 102. The EDU 102 includes a gearbox 104. An electric machine 106 is mounted to the gearbox 104 and configured to provide drive to an input shaft (not shown) of the gearbox 104. A drive electronics unit in the form of an inverter 108 is mounted to the gearbox 104 and configured to provide drive current to the electric machine 106.

In the embodiment shown, the electric machine 106 is mounted to a first lateral side of the gearbox 104, and the inverter 108 is mounted to a second lateral side of the gearbox 104 opposite the first lateral side.

In the illustrated embodiment, the EDU 102 has an elongate axis 110 extending generally through the gearbox 104. As best shown in Figures 2 and 4 to 7, the elongate axis 110 is defined in this embodiment by the longest dimension of the gearbox 104. As best shown in Figure 2, the EDU is substantially T-shaped in front elevation.

The vehicle 100 comprises a vehicle body 101, as described in more detail below. In this context, the vehicle body 101 is to be understood broadly as any portion of the vehicle 100 to which an electric drive unit (EDU) may be mounted. For example, the vehicle body may include a frame, subframe, chassis, bodywork or any other structural component(s) capable of supporting the weight of an EDU and reacting to the torque it generates.

The EDU 102 is connected to the vehicle body 101 via a plurality of mounts. The plurality of mounts comprises a drive electronics mount in the form of a first mount bracket 134 bolted directly to the first inverter 108 by way of bolts 142 screwed into corresponding threaded bosses 144 (see Figure 6) on the inverter 108. The first mount bracket 134 has an elastomeric mounting portion 131.

In the illustrated embodiment, the first mount bracket 134 connects only to the inverter 108. In other embodiments, the first mount bracket may connect to another part of the EDU in addition to the inverter 108. For example, the first mount bracket may connect to the inverter 108 and the gearbox 104. In the illustrated embodiment, the first mount bracket 134 is a separate component attached to the inverter 108 as described above. In other embodiments, the drive electronics mount may comprise a housing of the inverter 108. Similarly, in the illustrated embodiment, the second mount bracket 135 is a separate component attached to the electric machine 106, as described above. In other embodiments, the electric machine mount may comprise a housing of the electric machine 106.

In the illustrated embodiment, the plurality of mounts also comprises an electric machine mount in the form of a second mount bracket 135 bolted directly to the electric machine 106 by way of bolts 152 screwed into corresponding threaded bosses 153 (see Figure 7) on the electric machine 106. The second mount bracket 135 has an elastomeric mounting portion 136.

In the illustrated embodiment, the second mount bracket 135 connects only to the electric machine 106. In other embodiments, the second mount bracket may connect to another part of the EDU in addition to the electric machine 106. For example, the second mount bracket may connect to the electric machine 106 and the gearbox 104.

The first and second mount brackets 134 and 135 are positioned at opposite ends of a crossbar of the T-shape, and the gearbox 104 forms an upright of the T-shape.

In the illustrated embodiment, the first mount bracket 134 is a separate component attached to the inverter 108 as described above. In other embodiments, the drive electronics mount may comprise a housing of the inverter 108. Similarly, in the illustrated embodiment, the second mount bracket 135 is a separate component attached to the electric machine 106, as described above. In other embodiments, the electric machine mount may comprise a housing of the electric machine 106.

As best shown in Figures 4, 5, 7 and 8, in the illustrated embodiment a further mount in the form of third mount bracket 140 is bolted to a lower end of the gearbox 104 by way of bolts 145 screwed into corresponding threaded bosses 147. In the illustrated embodiment, the third mount bracket 140 is disposed in front of a lower portion of the upright of the T-shape.

In the illustrated embodiment, the third mount bracket 140 is attached to the gearbox 104. In other embodiments, the third mount bracket 140 may form part of the housing of the gearbox 104, or may be attached to, or form part of, another portion of the EDU 102. The third mount bracket 140 has an elastomeric mounting portion 146.

The vehicle body 101 comprises a crossmember 141 that extends between front shock towers 138 of the vehicle 100. The first mount bracket 134 is connected to the vehicle body 101 at a mounting point 137 on the crossmember 141 via its elastomeric mounting portion 131, and the second mount 135 is connected to the vehicle body 101 at a mounting point 139 on the crossmember 141 via its elastomeric mounting portion 136.

The vehicle body 101 also comprises a front subframe 133. The third mount bracket 140 is connected to a third mounting point 143 on the subframe 133 (see Figure 8), via its elastomeric mounting portion 146, at a position lower than the first and second mounts 134 and 135. As can be seen in Figure 8, the elastomeric mounting portion 146 of the third mount bracket 140 is bolted to the subframe 133 at either end of the elastomeric mounting portion 146.

In the illustrated embodiment, the mounting points 137 and 139 bear some of the EDU’s weight via the first mount bracket 134 and the second mount bracket 135, and the third mounting point 143 bears the remainder of the EDU’s weight via the third mount bracket 140.

Alternatively, the mounting points 137 and 139 may be configured to bear most of the EDU’s weight via the first mount bracket 134 and the second mount bracket 135. In that case, the third mounting point 143 may be largely or wholly for torque-reaction via the third mount bracket 140, bearing substantially none of the weight of the EDU 102. The EDU 102 may be mounted with its axis 110 at a pitch angle greater than 45°. In the illustrated embodiment, the pitch angle is substantially vertical. The word “vertical” in this context is used with its ordinary meaning, and is not necessarily limited to exactly 90°.

In the illustrated embodiment, the EDU 102 drives a set of front wheels 130 of the vehicle 100 via respective output shafts 151 of the gearbox 104. A centre of gravity of the EDU 102 is above the output shafts.

In the illustrated embodiment, the vehicle 100 comprises a further EDU 112. As best show in in Figures 9-12, the further EDU 112 includes a further gearbox 114. A further electric machine 116 is mounted to the further gearbox 114 and configured to provide drive to an input shaft (not shown) of the further gearbox 114. A further drive electronics unit in the form of a further inverter 118 is mounted to the further gearbox 114 and configured to provide drive current to the further electric machine 116.

In the embodiment shown, the further electric machine 116 is mounted to a first lateral side of the further gearbox 114, and the further inverter 118 is mounted to a second lateral side of the further gearbox 114 opposite the first lateral side.

In the illustrated embodiment, the further EDU 112 has an elongate axis 120 extending generally through the further gearbox 114. As best shown in Figures 9 and 10, the elongate axis 120 is defined in this embodiment by the longest dimension of the further gearbox 114. As best shown in Figure 13 the further EDU is substantially T-shaped in plan.

The further EDU 112 is mounted with its axis 120 at a further pitch angle, which may be less than 45°. In the illustrated embodiment, the further pitch angle is approximately horizontal. The word “horizontal” in this context is used with its ordinary meaning, and is not necessarily limited to exactly 0°. In the illustrated embodiment, the vehicle body 101 includes rear subframe 150 (see Figure 14).

In the illustrated embodiment, the further EDU comprises a plurality of mounts. The plurality of mounts comprises a drive electronics mount in the form of a fourth mount bracket 156. The fourth mount bracket 156 is bolted directly to the further inverter 118 by way of bolts 164 (see Figures 9, 13 and 14) screwed into corresponding threaded bosses 166 (see Figure 11) on the further inverter 118. The fourth mount bracket 156 attaches to a fourth mounting point 157 disposed on the rear subframe 150 (see Figure 14) of the vehicle 100 via its elastomeric mounting portion 173.

In the illustrated embodiment, the plurality of mounts further comprises an electric machine mount in the form of a fifth mount bracket 158. The fifth mount bracket 158 is bolted directly to the further electric machine 116 by way of bolts 168 (see Figure 10) screwed into corresponding threaded bosses 170 (see Figure 12) on the further electric machine 116. The fifth mount bracket 158 attaches to a fifth mounting point 159 disposed on the rear subframe 150 of the vehicle 100 via its elastomeric mounting portion 174.

The fourth and fifth mount brackets 156 and 158 are positioned at opposite ends of a crossbar of a T-shape formed by the further EDU 112 in plan (see Figure 13). The gearbox 114 forms an upright of the T-shape.

In the illustrated embodiment, a further mount is provided in the form of a sixth mount bracket 160. The sixth mount bracket 160 is a common bracket for two elastomeric mounting portions 175,176. The sixth mount bracket 160 is bolted directly to the further gearbox 114 by way of threaded bolts 165 (see Figures 9, 10, 13 and 14) screwed into corresponding threaded bosses 161 (see Figures 11 and 12). The sixth mount bracket 160 attaches to sixth and seventh mounting points 171,172 disposed on the rear subframe 150 of the vehicle 100 via its elastomeric mounting portions 175,176. Each of the fourth, fifth, and sixth mount brackets 156, 158, 160 is a combined weight bearing and torque-reaction mount that connects the further EDU 112 to the vehicle body 101 at its corresponding mounting point.

In the illustrated embodiment, the further EDU 112 is configured to drive a pair of rear wheels 132 of the vehicle.

Mounts for the front-mounted EDU 102 may consist solely of first, second and third elastomeric mounts in the specific geometric relationships illustrated. In addition, there are specific advantages that may flow from specifically providing a first weight-bearing mount on a first upper lateral side of the EDU, a second weight-bearing mount on a second upper lateral side of the EDU opposite the first upper lateral side of the EDU, and a third torque-reaction mount at a lower end of the EDU. These advantages include effective mounting of the EDU to the vehicle, and especially a front end of the vehicle, in a compact manner that may result in production and installation efficiencies.

Similarly, mounts for the rear-mounted EDU 112 may consist solely of first, second, third and fourth mounts (corresponding to the illustrated fourth, fifth, sixth and seventh elastomeric mounts in the illustrated embodiment) in the specific geometric relationships illustrated. In addition, there are specific advantages that flow from providing a first weight-bearing and torque-reaction mount on a first lateral side of the EDU, a second weight-bearing and torque-reaction mount on a second lateral side of the EDU opposite the first lateral side of the EDU, and third and fourth weight-bearing and torque-reaction mounts at an end of the EDU opposite that to which the first and second mounts are located. These advantages include effective mounting of the EDU to the vehicle, and especially a rear end of the vehicle, in a compact manner that may result in production and installation efficiencies.

The skilled person will appreciate that each mount may be attached to its respective mounting point with multiple bolts via its respective elastomeric portion. In the illustrated embodiment, the EDU 102 attaches to the vehicle at three attachment points via its three elastomeric mounting portions and the EDU 112 attaches to the vehicle at four attachment points via its four elastomeric mounting portions.

The illustrated embodiment has first and second EDUs. It will be appreciated, however, that a vehicle according to aspects of the invention may comprise only one EDU, which may be arranged and configured to drive one or more wheels. For example, a single EDU may drive a pair of front wheels or a pair of back wheels. By way of an additional drive mechanism (such as a drive shaft, for example) a single EDU can also drive more than one pair of wheels. In yet other embodiments, one or more EDUs may drive only a single wheel, or multiple wheels. In short, any combination of EDU(s) and driven wheel(s) may be employed, depending upon the particular functional requirements of an embodiment.

Although the illustrated vehicle 100 is a car, the invention may find application in other types of vehicles, such as trucks and vans.

Although the invention has been described with reference to specific examples, it will be appreciated that the invention may be embodied in many other forms that fall within the scope of the appended claims.

Claims

1. A vehicle comprising: a vehicle body; and an electric drive unit, the electric drive unit comprising: a gearbox; an electric machine mounted to the gearbox and configured to provide drive to the gearbox; and a drive electronics unit mounted to the gearbox and configured to provide drive current to the electric machine; wherein the electric drive unit is mounted to the vehicle body via a plurality of mounts, the plurality of mounts including a drive electronics mount disposed on the drive electronics unit and connecting the electric drive unit to the vehicle body; and wherein the electric drive unit is substantially T-shaped in plan, wherein the drive electronics unit and electric machine are positioned at opposite ends of a crossbar of the T-shape, and the gearbox forms an upright of the T-shape.

2. The vehicle of claim 1, wherein the drive electronics mount comprises a separate unit attached to a housing of the drive electronics unit.

3. The vehicle of claim 1 or claim 2, wherein the drive electronics mount comprises part of a housing of the drive electronics unit.

4. The vehicle of any preceding claim, wherein the drive electronics mount is attached to the electric drive unit only via the drive electronics unit.

5. The vehicle of any preceding claim, wherein the mounts include an electric machine mount disposed on the electric machine and connecting the electric drive unit to the vehicle.

6. The vehicle of claim 5, wherein the electric machine mount comprises a separate unit attached to a housing of the electric machine.

7. The vehicle of claim 5 or claim 6, wherein the electric machine mount comprises part of a housing of the electric machine.

8 The vehicle of any of claims 5 to 7, wherein the electric machine mount is attached to the electric drive unit only via the electric machine.

9. The vehicle of any preceding claim, wherein the plurality of mounts includes at least one further mount.

10. The vehicle of claim 9, wherein the electric drive unit is substantially T-shaped in front elevation, wherein the drive electronics unit and electric machine are positioned at opposite ends of a crossbar of the T-shape, and the gearbox forms an upright of the T- shape.

11. The vehicle of any preceding claim, comprising a further electric drive unit, the further electric drive unit comprising: a further gearbox; a further electric machine mounted to the further gearbox and configured to provide drive to the further gearbox; and a further drive electronics unit mounted to the further gearbox and configured to provide drive current to the further electric machine; wherein the further electric drive unit is mounted to the vehicle body via a plurality of further mounts, the further mounts including a further drive electronics mount disposed on the further drive electronics unit and connecting the further electric drive unit to the vehicle body.

12. The vehicle of claim 11, wherein: a housing of the drive electronics unit is the same as a housing of the further drive electronics unit; the drive electronics mount and the further drive electronics mount are different to each other.

13. The vehicle of any preceding claim, wherein the electric drive unit and/or the further electric drive unit is/are configured to drive a pair of rear wheels of the vehicle or a pair of front wheels of the vehicle.