U.S. patent application number 14/125867 was filed with the patent office on 2014-05-01 for drive system with ventilation.
This patent application is currently assigned to Schaeffler Technologies AG & Co. KG. The applicant listed for this patent is Raphael Fisher, Mark Lauger, Tobias Vogler. Invention is credited to Raphael Fisher, Mark Lauger, Tobias Vogler.
Application Number | 20140117743 14/125867 |
Document ID | / |
Family ID | 47426508 |
Filed Date | 2014-05-01 |
United States Patent
Application |
20140117743 |
Kind Code |
A1 |
Vogler; Tobias ; et
al. |
May 1, 2014 |
DRIVE SYSTEM WITH VENTILATION
Abstract
A drive system, in particular a drive system of a wheel hub, for
a motor vehicle, in particular an electric and/or hybrid motor
vehicle, the drive system including an electric motor. In order to
prevent moisture from accumulating in an internal chamber (1) of
the drive system, the drive system includes a ventilation device
(20) for aerating and de-aerating the interior chamber (1) of the
drive system. The ventilation device (20) includes at least one air
supply device (21) for supplying air into the internal chamber (1)
of the drive system and at least one air removal device (22) for
removing air from the internal chamber (1) of the drive system.
Inventors: |
Vogler; Tobias;
(Herzogenaurach, DE) ; Fisher; Raphael;
(Herzogenaurach, DE) ; Lauger; Mark;
(Grossweinstein, DE) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Vogler; Tobias
Fisher; Raphael
Lauger; Mark |
Herzogenaurach
Herzogenaurach
Grossweinstein |
|
DE
DE
DE |
|
|
Assignee: |
Schaeffler Technologies AG &
Co. KG
Herzogenaurach
DE
|
Family ID: |
47426508 |
Appl. No.: |
14/125867 |
Filed: |
April 11, 2012 |
PCT Filed: |
April 11, 2012 |
PCT NO: |
PCT/EP2012/056483 |
371 Date: |
December 12, 2013 |
Current U.S.
Class: |
301/6.5 |
Current CPC
Class: |
Y02T 10/86 20130101;
B60B 2900/311 20130101; B60B 3/16 20130101; B60B 3/147 20130101;
B60K 2007/0038 20130101; B60K 2007/0092 20130101; B60B 2900/111
20130101; B60K 7/0007 20130101 |
Class at
Publication: |
301/6.5 |
International
Class: |
B60K 7/00 20060101
B60K007/00 |
Foreign Application Data
Date |
Code |
Application Number |
Jul 7, 2011 |
DE |
102011107395.0 |
Aug 26, 2011 |
DE |
102011081660.7 |
Claims
1-10. (canceled)
11. A drive system for a vehicle, the drive system having at least
one drive system internal chamber, the drive system comprising: an
electric motor having a stator and a rotor; and a ventilation
device for aerating and de-aerating the drive system internal
chamber, the ventilation device including at least one air supply
device for supplying air to the drive system internal chamber and
at least one air removal device for removing air from the drive
system internal chamber.
12. The drive system as recited in claim 11 wherein the air supply
device is situated above a drive axis of the drive system or the
air removal device is situated below the drive axis.
13. The drive system as recited in claim 11 wherein the air supply
device include at least one filter or at least one dryer.
14. The drive system as recited in claim 13 wherein the air supply
device includes a particle filter or a moisture filter or a gas
filter.
15. The drive system as recited in claim 11 wherein the air supply
device is designed as an active or temporarily active air supply
device for at least temporarily actively supplying air to the drive
system internal chamber.
16. The drive system as recited in claim 15 wherein the air supply
device is temporarily connectable or permanently connected to a
ventilation system of the vehicle or is temporarily connectable to
a maintenance ventilation system.
17. The drive system as recited in claim 16 wherein the sir supply
device is connected to an air conditioning system of the
vehicle.
18. The drive system as recited in claim 11 wherein air from a
vehicle interior, is suppliable to the drive system internal
chamber with the aid of the air supply device.
19. The drive system as recited in claim 18 wherein the air is from
a passenger cell or a storage compartment.
20. The drive system as recited in claim 19 wherein the air is from
a trunk.
21. The drive system as recited in claim 11 wherein the air supply
device is situated on a stationary drive system element of the
drive system.
22. The drive system as recited in claim 21 wherein the stationary
drive system element of the drive system is fixedly connected to
the stator of the electric motor.
23. The drive system as recited in claim 22 wherein the air supply
device is on a stator retaining plate.
24. The drive system as recited in claim 11 wherein the air supply
device includes an air supply connecting element for the airtight
connection of the air supply device to the drive system internal
chamber, or the air removal device includes an air removal
connecting element for the airtight connection of the air removal
device to the drive system internal chamber.
25. The drive system as recited in claim 11 wherein the air supply
device includes a valve, or the air removal device includes a
further valve.
26. The drive system as recited in claim 25 wherein the air removal
device includes a check valve.
27. The drive system as recited in claim 25 wherein the air removal
device includes the further valve, the further valve being designed
to allow air to flow out of the drive system internal chamber and
to prevent air from flowing into the drive system internal
chamber.
28. The drive system as recited in claim 25 wherein the air supply
device includes a check valve.
29. The drive system as recited in claim 25 wherein the air supply
device has the valve, the valve allowing air to flow into the drive
system internal chamber and to prevent air from flowing out of the
drive system internal chamber.
30. The drive system as recited in claim 11 further comprising a
friction brake.
31. The drive system as recited in claim 11 wherein drive system
internal chamber surrounds a gap between the stator and the rotor
of the electric motor or surrounds a friction brake.
32. The drive system as recited in claim 31 wherein the gap is an
air gap.
33. A wheel hub drive system comprising the drive system as recited
in claim 11.
34. An electric or hybrid vehicle comprising the drive system as
recited in claim 11.
Description
[0001] The present invention relates to a drive system for a
vehicle, in particular for an electric and/or a hybrid vehicle.
BACKGROUND
[0002] Interest in electric vehicles has increased more and more in
recent years, in particular due to a growing environmental
awareness.
[0003] Central and wheel-proximal electric motors as well as
electric wheel hub drives, among other things, may be used in
electric cars. Electric wheel hub drives are a special design of an
electric motor. An electric wheel hub drive includes an electric
motor which is built directly into a wheel of a vehicle and
simultaneously supports the wheel hub in such a way that a part of
the motor rotates together with the wheel.
[0004] In an internally rotating wheel hub drive, a so-called
internal rotor, the rotor may be situated, for example, inside the
stator. In an externally rotating wheel hub drive, a so-called
external rotor, the rotor may be situated, for example, outside the
stator.
[0005] Since wheel-proximal electric motors and wheel hub drives
are situated in the surroundings of a vehicle wheel, they may be
exposed to high humidity or even moisture, in particular during
rainy weather.
SUMMARY OF THE INVENTION
[0006] It is an object of the present invention to provide a drive
system, in particular a wheel hub drive system, for a vehicle, in
particular for an electric and/or hybrid vehicle, having at least
one drive system internal chamber which includes an electric motor
having a stator and a rotor.
[0007] The present invention provides that the drive system
includes a ventilation device for aerating and de-aerating the
drive system internal chamber of the drive system, the ventilation
device including at least one air supply device for supplying air
to the drive system internal chamber and at least one air removal
device for removing air from the drive system internal chamber.
[0008] Within the scope of the present invention, air may be
understood to be a natural air atmosphere or ambient air as well as
an artificial atmosphere having, for example, a high concentration
of inert gas. In the specific embodiment explained below, in
particular, in which the drive system is designed for active
aeration during maintenance work, an inert gas or a gas mixture
containing inert gas may be used for active ventilation. For
example, nitrogen, argon and/or helium, in particular nitrogen, may
be used as inert gas.
[0009] A targeted air exchange between the drive system and its
surroundings may be advantageously ensured by the ventilation
device according to the present invention. Pressures which may
build up in the drive system, in particular due to climatic
conditions and/or temperature fluctuations, for example in the
event of a cool external temperature and an elevated inner
temperature which results in significant air expansion, for example
due to braking actions with the aid of a friction brake, may be
advantageously compensated with the aid of the ventilation device.
Thus, pressure-induced and possibly heat-induced damage to
sensitive drive system elements may be prevented, for example the
lifting of seals. In addition, moisture which penetrates the drive
system, possibly due to humidity condensation or possible leakages,
may be advantageously removed with the aid of the ventilation
device.
[0010] Within the scope of one specific embodiment, the air supply
device(s) is/are situated above a drive axis of the drive system.
For example, the air supply device(s) may be situated in relation
to the drive axis in a position range from .gtoreq.9 o'clock to
.ltoreq.3 o'clock, in particular from .gtoreq.10 o'clock to
.ltoreq.2 o'clock, for example from .gtoreq.11 o'clock to .ltoreq.1
o'clock, for example approximately at 12 o'clock. Situating the air
supply devices above the drive axis has the advantage that less
spray water tends to be applied to this area, and an introduction
of moisture may thus be reduced or even prevented.
[0011] Within the scope of another specific embodiment, the air
removal device(s) is or are situated below a drive axis of the
drive system. For example, the air removal device(s) may be
situated in relation to the drive axis in a position range from
.gtoreq.3 o'clock to .ltoreq.9 o'clock, in particular from
.gtoreq.4 o'clock to .ltoreq.8 o'clock, for example from .gtoreq.5
o'clock to .ltoreq.7 o'clock, for example approximately at 6
o'clock, Situating the air removal devices below the drive axis has
the advantage that moisture tends to be deposited in this area and
may thus be particularly effectively removed from this area.
[0012] Air supply devices situated above the drive axis and air
removal devices situated below the drive axis have, in combination,
the advantage that a greater amount of flow passes through the
volume of the drive system internal chamber, and the flowing air is
able to absorb more liquid and transport it out of the system.
[0013] Within the scope of another specific embodiment, the air
supply device(s) includes or include at least one filter, in
particular a particle filter and/or a moisture filter and/or a gas
filter. This makes it possible to advantageously prevent
contamination and/or moisture and/or chemically aggressive gases
from being introduced into the drive system internal chamber of the
drive system. A filter based on a water-impermeable but vapor
diffusion-open diaphragm, for example, may be used to filter out
moisture in the liquid aggregate state and/or particles. For
example, a diaphragm based, for example, on polytetrafluoroethylene
(PTFE), from, for example, the Gore Company ("Gore-Tex"), Germany,
may be used as a filter for removing moisture in the liquid
aggregate state and/or particles.
[0014] Within the scope of another specific embodiment, the air
supply device(s) includes or include at least one dryer. The dryer
may be based, for example, on water condensation and, for example,
remove moisture from air due to the fact that the air is cooled to
a lower temperature. For example, an air conditioning system of the
vehicle may function as the dryer. However, it is also possible for
the dryer to be designed on the basis of a physically and/or
chemically water-absorbing material. If necessary, a dryer of this
type may simultaneously function as a filter, or a filter of this
type may simultaneously function as a dryer. Consequently, the air
supply device(s) may also have at least one combined filter-dryer
unit.
[0015] The air supply device(s) may furthermore include an air
supply line, for example an air supply hose.
[0016] For this purpose, the air supply device(s) may be designed
in such a way that air may be passively and/or actively supplied to
the drive system internal chamber. The air supply device(s) may
thus be designed as active and/or passive air supply device(s). For
example, the air supply device(s) may be completely active,
temporarily active and otherwise passive or completely passive air
supply device(s).
[0017] A passive design of the air supply device(s) is explained in
greater detail below in connection with a check valve system.
[0018] An active design of the air supply device(s) may be carried
out, for example, by the fact that the air supply device is
permanently or temporarily connected or connectable to a
ventilation system of the vehicle or to a maintenance ventilation
system. An active ventilation of the drive system internal chamber
may thus be advantageously achieved. The active ventilation may
take place, for example, using a ventilation system provided in the
vehicle and/or a maintenance ventilation system connected during
maintenance.
[0019] Within the scope of another specific embodiment, the air
supply device(s) is or are designed as active or temporarily active
air supply devices for the at least temporary, active supply of air
to the drive system internal chamber. In particular, the air supply
device(s) may be temporarily connectable or permanently connected
to a ventilation system of the vehicle, for example an air
conditioning system of the vehicle. Alternatively or additionally,
the air supply device(s) may be temporarily connectable to a
maintenance ventilation system. A cleaning/drying of the system may
thus advantageously take place without having to disassemble the
system.
[0020] Within the scope of another specific embodiment, air from a
vehicle interior, for example from a passenger cell, or a storage
compartment, for example a trunk, may be supplied to the drive
system internal chamber with the aid of the air supply line.
[0021] Within the scope of another specific embodiment, the air
supply device(s) is or are situated on a stationary, i.e.,
non-rotatable, drive system element of the drive system, for
example on a drive system element of the drive system which is, in
particular, rotatably fixedly connected to the stator of the
electric motor, for example on a stator retaining plate.
[0022] The air removal device(s) may also be situated on the same
or on a different stationary drive system element of the drive
system, for example on a stationary drive system element of the
drive system which is, in particular, rotatably fixedly connected
to the stator of the electric motor, for example on a stator
retaining plate.
[0023] However, since the air removal device(s) does/do not have to
be connected to additional elements, for example the vehicle, the
air removal device(s) may also be readily situated on a rotatable
drive system element of the drive system, for example on a
rotatable drive system element of the drive system which is, in
particular, rotatably fixedly connected to the rotor of the
electric motor, for example a wheel rim, a cover or a rotor
support.
[0024] Within the scope of another specific embodiment, the air
supply device(s) includes or include an air supply connecting
element for the airtight connection of the air supply device to the
drive system internal chamber. For example, the air supply
connecting element may be fastenable or fastened to a recess in a
wall delimiting the drive system internal chamber, for example in a
stator retaining plate, in such a way that air is able to enter the
drive system element internal chamber through the air supply
connecting element, the area between the air supply connecting
element and the wall delimiting the recess and the drive system
internal chamber being airtight and, in particular, also
water-tight.
[0025] Within the scope of another specific embodiment, the air
removal device(s) includes or include an air removal connecting
element for the airtight connection of the air removal device to
the drive system internal chamber. For example, the air removal
connecting element may be fastenable or fastened to a recess in a
wall delimiting the drive system internal chamber, for example in
the stator retaining plate and/or in the wheel rim, in the cover or
in the rotor support, in such a way that air is able to exit the
drive system element interior through the air removal connecting
element, the area between the air removal connecting element and
the wall delimiting the recess and the drive system internal
chamber being airtight and, in particular, also water-tight.
[0026] A directed air movement and thus a targeted exchange of air
may advantageously be achieved by using valves, in particular check
valves, in the air supply devices and/or air removal devices.
[0027] For example, the air supply devices may be provided with
valves which ensure that air is able to only flow in but not flow
out, while the air removal devices may be provided with valves
which ensure that air is able to only flow out but not flow in.
When the air in the interior of the system is heated, the air may
thereby be forced to flow out through the preferably lower air
removal devices and remove any water and/or dirt which may be
located in the system. Upon cooling, the air removal device(s) may
be blocked, and air may be drawn back in through the, in
particular, upper air supply device(s).
[0028] Within the scope of another specific embodiment, the air
supply device(s) includes or include a valve, in particular a check
valve. In particular, the valve or the check valve of the air
supply device may be designed to allow air to flow into the drive
system internal chamber and to prevent air from flowing out of the
drive system internal chamber.
[0029] Within the scope of another specific embodiment, the air
removal device(s) includes or include a valve, for example a check
valve. In particular, the valve or the check valve of the air
removal device may be designed to allow air to flow out of the
drive system internal chamber and to prevent air from flowing into
the drive system internal chamber.
[0030] In particular, a water-impermeable but vapor diffusion-open
diaphragm, which is air-permeable in only one direction and
air-impermeable in the other direction, may be used as the valve,
in particular the check valve. For example, a diaphragm based, for
example, on polytetrafluoroethylene (PTFE), from, for example, the
Gore company ("Gore-Tex"), Germany, may be used as the valve, in
particular the check valve.
[0031] The ventilation device may include, in particular, multiple
air removal devices. It is possible for only one air supply device
but multiple air removal devices to be provided, for example in the
form of valves, in particular check valves.
[0032] Alternatively or in addition to multiple air removal
devices, the ventilation device may include multiple air supply
devices, for example in the form of valves, in particular check
valves.
[0033] Within the scope of another specific embodiment, the drive
system also includes a friction brake. In particular, the friction
brake may be integrated within a vehicle wheel, in particular
within the electric motor, for example within the rotor of the
electric motor. The friction brake may be, for example, a drum
brake or a disc brake.
[0034] The drive system internal chamber is preferably at least
partially, in particular completely, designed as a closeable or
closed chamber. Closeable may be understood to mean that the drive
system internal chamber is designed to be able to be temporarily
opened and then closed again. For example, the drive system
internal chamber may be open during assembly and/or maintenance and
closeable after assembly and/or maintenance.
[0035] Within the scope of another specific embodiment, the drive
system internal chamber surrounds a gap, in particular an air gap,
between the stator and the rotor of the electric motor, and/or a
friction brake of the drive system.
[0036] If necessary, the drive system may also include two or more
drive system internal chambers. For example, the drive system may
include a drive system internal chamber which surrounds the gap, in
particular the air gap, between the stator and the rotor and may
also include another drive system internal chamber which surrounds
the friction brake. It is not necessary to equip the drive system
with two ventilation systems. Instead, the drive system internal
chambers may be connected in series between the air supply
device(s) and the air removal device(s), it being possible to
provide at least one airlock between the drive system internal
chambers. The airlock(s) may be provided with a similar design as
the air supply devices.
[0037] For example, an airlock may include a valve, in particular a
check valve, and/or an airlock connecting element for the airtight
connection of the airlock between two drive system internal
chambers, and/or a filter, for example a particle filter and/or a
moisture filter and/or a gas filter, and/or a dryer.
[0038] In particular, an airlock may include or consist of a valve,
for example a check valve, which, in particular, permits air to
flow into the downstream drive system internal chamber and prevents
air from flowing out of the downstream drive system internal
chamber into the upstream drive system internal chamber. A drive
system element chamber which surrounds the gap between the rotor
and the stator is preferably an upstream drive system element
chamber, and/or the drive system element chamber which surrounds
the friction brake is a downstream drive system element chamber.
The drive system element chamber which has the moisture-sensitive
components may thus advantageously be provided with fresher or
dryer air.
BRIEF DESCRIPTION OF THE DRAWINGS
[0039] The present invention is explained in greater detail below
with reference to the appended drawing. The drawing and its
description are intended to be used to illustrate the subject
matters of the present invention and not to be used to limit the
present invention in any way.
[0040] FIG. 1 shows a schematic cross section of one specific
embodiment of a drive system according to the present invention,
including a ventilation device.
DETAILED DESCRIPTION
[0041] FIG. 1 shows a specific embodiment of a drive system
according to the present invention for an electric and/or hybrid
vehicle which is designed, in particular, as a wheel hub drive
system and has a drive system internal chamber 1.
[0042] FIG. 1 shows that drive system internal chamber 1 surrounds
an electric motor having a stator 10 and a rotor 11. Stator 10 is
situated in a stationary, i.e., non-rotatable, manner, and rotor 11
is rotatably situated, in particular around a drive axis A of the
drive system.
[0043] FIG. 1 shows that a gap S, in particular an air gap, is
present between stator 10 and rotor 11. For efficiency reasons, the
gap between stator 10 and rotor 11 is designed to be so small that
a grinding of rotor 11 against stator 10 is nevertheless
prevented.
[0044] FIG. 1 shows that the drive system internal chamber within
the scope of the illustrated specific embodiment also surrounds a
friction brake 13a, 13b, 13c, which is designed as a drum brake and
which includes a brake drum 13a, brake shoes 13b and a brake
cylinder 13c.
[0045] FIG. 1 furthermore illustrates that stator 10 is, in
particular, rotatably fixedly connected to a stationary inner ring
14a of a wheel bearing via a stator retaining plate 12. The wheel
bearing furthermore has an outer ring 14b which is rotatably
supported via rolling bodies 14c. Rolling bodies 14c are situated
in rolling bearing cages, the wheel bearing being braceable with
the aid of a bracing device 14e which interacts with a rolling
bearing inner ring 14d. The wheel bearing also has fastening
elements 14f for fastening the wheel bearing to the vehicle.
[0046] FIG. 1 also shows that rotor 11 is connected to rotatable
outer ring 14b of the wheel bearing via a rotor support 15. The
rotor support is connected to rotatable outer ring 14b of the wheel
bearing as well as to a wheel rim (not illustrated) with the aid of
a screw connection 16. Rotor support 15 is also connected to brake
drum 13a with the aid of another screw connection 17. However,
brake shoes 13b and brake cylinder 13c are connected to stator
retaining plate 12.
[0047] FIG. 1 furthermore shows that the drive system has a cover
18. This cover is situated, in particular, on the outside and may
be used to temporarily open the drive system internal chamber
during maintenance work.
[0048] FIG. 1 furthermore shows that stator 10 has two winding head
areas 10a in addition to a stator lamination stack 10 situated in
the central area.
[0049] FIG. 1 shows, in particular, that the drive system has a
ventilation device 20 for aerating and de-aerating drive system
internal chamber 1, which includes an air supply device 21 for
supplying air to drive system internal chamber 1 and an air removal
device 22 for removing air from drive system internal chamber
1.
[0050] FIG. 1 illustrates that air supply device 21 is situated
above drive axis A of the drive system, in particular approximately
in the 12-o'clock position, while air removal device 22 is situated
below the drive axis of the drive system, in particular
approximately in the 6-o'clock position. Within the scope of the
illustrated specific embodiment, both air supply device 21 and air
removal device 22 are fastened to a stationary drive system element
of the drive system, namely stator retaining plate 12. Air supply
device 21 includes an air supply connecting element 21a for the
airtight connection of air supply device 21 to drive system
internal chamber 1, and air removal device 22 includes an air
removal connecting element 22a for the airtight connection of air
removal device 22 to drive system internal chamber 1.
[0051] FIG. 1 shows that air supply device 21 furthermore has a
hose-type air supply line 21b via which air supply device 21 may be
temporarily connected to a ventilation system of the vehicle, for
example an air conditioning system of the vehicle, or a maintenance
ventilation system, or which may be temporarily or permanently
connected to a vehicle interior, for example a passenger cell or a
storage compartment, for example a trunk, of the vehicle, in
particular to actively and/or passively supply air to drive system
internal chamber 1.
[0052] FIG. 1 finally shows that air removal device 22 includes a
valve, in particular a check valve 22b. The valve or check valve
22b is designed to allow air to flow out of drive system internal
chamber 1 and to prevent air from flowing into drive system
internal chamber 1. The valve is connected to air removal
connecting element 22a with the aid of a connecting piece 22c.
LIST OF REFERENCE NUMERALS
[0053] 1 Drive internal chamber [0054] 10 Stator of the electric
motor, in particular a stator lamination stack [0055] 10a Winding
head area of the stator [0056] 11 Rotor of the electric motor
[0057] A Drive axis [0058] S Gap between the stator and rotor of
the electric motor [0059] 12 Stator retaining plate [0060] 13a
Brake drum of the friction brake [0061] 13b Brake shoes of the
friction brake [0062] 13c Brake cylinder of the friction brake
[0063] 14a Stationary inner ring of the wheel bearing [0064] 14b
Rotatable outer ring of the wheel bearing [0065] 14c Rolling body
of the wheel bearing [0066] 14d Rolling bearing inner ring [0067]
14e Rolling bearing bracing device [0068] 14f Fastening element for
fastening the wheel bearing to the vehicle [0069] 15 Rotor support
[0070] 16 Screw connection [0071] 17 Screw connection [0072] 18
Cover [0073] 20 Ventilation device [0074] 21 Air supply device
[0075] 21a Air supply connecting element [0076] 21b Air supply line
[0077] 22 Air removal device [0078] 22a Air removal connecting
element [0079] 22b Check valve of the air removal device [0080] 22c
Connecting piece of the air removal device
* * * * *