U.S. patent application number 14/796261 was filed with the patent office on 2016-01-21 for coolant pump with heat sinking to coolant.
The applicant listed for this patent is BorgWarner Inc.. Invention is credited to Stephen BOHAN, Shiwei QIN.
Application Number | 20160017894 14/796261 |
Document ID | / |
Family ID | 55074207 |
Filed Date | 2016-01-21 |
United States Patent
Application |
20160017894 |
Kind Code |
A1 |
QIN; Shiwei ; et
al. |
January 21, 2016 |
COOLANT PUMP WITH HEAT SINKING TO COOLANT
Abstract
A vehicle coolant pump with heat protection for the internal
electronics and circuit boards for operation of the coolant pump.
Gap fillers positioned adjacent said electronics and circuit boards
transfer heat to the coolant fluid in the engine.
Inventors: |
QIN; Shiwei; (Battle Creek,
MI) ; BOHAN; Stephen; (Charlotte, MI) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
BorgWarner Inc. |
Auburn Hills |
MI |
US |
|
|
Family ID: |
55074207 |
Appl. No.: |
14/796261 |
Filed: |
July 10, 2015 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
62024492 |
Jul 15, 2014 |
|
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|
Current U.S.
Class: |
417/374 ;
417/423.8 |
Current CPC
Class: |
F04D 13/02 20130101;
F04D 13/0686 20130101; F04D 29/5813 20130101; F01P 5/10 20130101;
F01P 7/14 20130101; F04D 13/06 20130101; F04D 29/5893 20130101;
F01P 3/20 20130101 |
International
Class: |
F04D 29/58 20060101
F04D029/58; F04D 29/22 20060101 F04D029/22; F01P 3/20 20060101
F01P003/20; F01P 5/10 20060101 F01P005/10; F01P 7/14 20060101
F01P007/14; F04D 13/06 20060101 F04D013/06; F04D 29/42 20060101
F04D029/42 |
Claims
1. A cooling system for a vehicle engine, comprising: (a) a coolant
pump, said coolant pump comprising a drive mechanism and a driven
mechanism with said drive mechanism comprising a mechanical drive
mechanism, and said driven mechanism comprising an electric motor,
said electric motor positioned in a motor housing; (b) a control
system for operating said coolant pump, said control system
comprising at least one temperature sensor, an ECU, and a circuit
board; and (c) a gap filler positioned in said motor housing and in
contact with said circuit board; wherein heat from said circuit
board is transferred through said gap filler and said motor
housing, and into a coolant fluid.
2. The cooling system as described in claim 1 wherein said coolant
pump is a dual mode coolant pump.
3. The cooling system as described in claim 1 wherein said electric
motor is a brushless DC motor.
4. The cooling system as described in claim 1 wherein said motor
housing has at least one wall member which is positioned between
said circuit board and the coolant fluid, and wherein said gap
filler is positioned between said at least one wall member and said
circuit board.
5. The cooling system as described in claim 1 wherein a plurality
of recesses are provided in a first side of said at least one wall
member which is in contact with a coolant fluid, and wherein said
gap filler is positioned on the opposite side of said first side of
at least one wall member.
6. The cooling system as described in claim 5 wherein the wall
thickness in bottoms of said recesses is about 5 to 20
millimeters.
7. The cooling system as described in claim 1 further comprising a
shaft member and an impeller member, said shaft member being
selectively driven by said drive mechanism and said driven
mechanism.
8. The cooling system as described in claim 7 wherein said shaft
member is supported in said coolant pump by a pair of bearing
members, and said electric motor is positioned between said bearing
members.
9. The cooling system as described in claim 1 wherein operation of
said coolant pump is controlled at least in part by control
logic.
10. The cooling system as described in claim 1 wherein said
mechanical drive mechanism includes a solenoid member and a
friction clutch member.
11. The cooling system as described in claim 10 wherein activation
of said solenoid member prevents said mechanical drive member from
rotating said shaft member.
12. The cooling system as described in claim 10 wherein activation
of said solenoid members allows said mechanical drive member to
rotate said shaft member.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] The present application claims benefit of U.S. Patent
Application 62/024,492 filed on Jul. 15, 2014.
TECHNICAL FIELD
[0002] The present invention is related to vehicle coolant pumps,
and more particularly to improved coolant pumps with heat
protection.
BACKGROUND
[0003] Coolant pumps for circulating cooling fluids in vehicles and
other cooling systems are in constant use today. There are various
types of coolant pumps, most of which work to various degrees of
satisfaction.
[0004] Some coolant pumps contain electrical systems and/or
electromagnetic components and systems, and thus contain heat
sensitive electronic components, such as circuit boards. This is
particularly true with dual mode coolant pumps that may contain
both electric motors and electromagnetic mechanisms. If the
electrical and electronic components and systems are not maintained
within conventional operating temperatures, the coolant pumps could
be ineffective or fail.
[0005] There is thus a need to provide coolant pumps with improved
methods of protecting electric or electronic components and systems
from excessive heat.
SUMMARY OF THE INVENTION
[0006] It is an objective of the present invention to provide an
improved coolant pump that meets these needs and provides benefits
and advantages over known coolant pumps.
[0007] In a preferred embodiment of the invention, a dual mode
coolant pump is provided which selectively rotates an impeller in a
coolant fluid housing. The dual mode coolant pump includes housings
in which an electric motor drive mechanism and a mechanical drive
mechanism for rotating the impeller are positioned. The coolant
fluid housing is attached to the vehicle engine and has an inlet
port for receipt of coolant fluid and an outlet port for transfer
of the coolant fluid into the engine block.
[0008] The electric motor, which preferably is a brushless DC
motor, and the electromagnetic clutch mechanism for the mechanical
drive mechanism are both operated electrically. A circuit board
(CB) is located in the coolant pump housing adjacent the coolant
fluid housing, and contains electronic components for operating the
electric motor and electromagnetic clutch mechanism. Power is
supplied from the vehicle electrical systems, including an
electronic control unit (ECU). If electrical power is absent, the
electric motor can be powered by the vehicle battery.
[0009] A gap filler is positioned in the pump housing adjacent to,
and in contact with, the circuit board. The gap filler acts as a
heat sink and transfers heat from the circuit board and its
components through the pump housing and into the coolant fluid.
Since typically the coolant fluid is at a temperature lower than
the temperatures of the circuit board components, this embodiment
of the invention protects the heat sensitive electronic components
by maintaining them within their acceptable temperature limits.
[0010] Further embodiments of the invention as well as additional
features and benefits of the invention will be disclosed below in
the following written description and accompanying drawings,
together with the appended claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] FIG. 1 depicts an embodiment of the invention.
[0012] FIG. 2 is an exploded view of the embodiment of FIG. 1.
[0013] FIG. 3 is a cross-sectional view of the coolant pump
depicted in FIG. 1.
[0014] FIG. 4 schematically depicts a cooling system and an
associated control system relative to an embodiment of the present
invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0015] A perspective view of an embodiment of the present invention
10 is shown in FIG. 1, and an exploded view is depicted in FIG. 2.
The embodiment includes a dual mode coolant pump 20 and an impeller
housing 30. The impeller housing 30 is adapted to be connected to,
or at least be in fluid communication with, a vehicle engine block
40.
[0016] The coolant pump 20 includes a motor housing 22, an electric
motor 24, a solenoid housing 26, a friction clutch mechanism 33 (as
better shown in FIG. 3) and a pulley member 29. The pulley member
29 is adapted to be rotated by an engine belt. An engine belt for
this purpose is shown in FIG. 4 and designated by reference number
31. The engine belt is also attached to a pulley member 32
positioned on the vehicle engine block 40. The pulley member 29 is
rotated by the engine at a speed ("input speed") determined by a
pulley ratio.
[0017] The coolant pump 20 is depicted in cross-section in FIG. 3.
A preferred dual mode coolant pump that can be utilized with the
present invention is disclosed and discussed in detail in U.S.
patent application Ser. No. 14/149,683, filed on Jan. 7, 2014, and
entitled "Accessory Drive With Friction Clutch and Electric Motor",
the disclosure of which is hereby incorporated herein by
reference.
[0018] An electric motor 24 is positioned in the motor housing 22.
The motor housing is preferably made of a metal material with good
thermal conductivity, such as aluminum. The electric motor is
preferably a brushless DC motor, and includes a coil-type stator
member 25 and a rotor member 27. The rotor member is fixedly
attached to central pump shaft member 28.
[0019] A solenoid member 34 is positioned in the solenoid housing
26. The solenoid housing is preferably made of a metal material,
such as low carbon steel.
[0020] The electronics for electric motor 24 and solenoid member 34
are contained in the circuit board ("CB") 50. The circuit board
contains the electronic components which electrically control the
operation of the electric motor and the solenoid member, including
turning them on and off. Power from the circuit board 50 is
supplied to the electric motor 24 through lead frame 52, and to the
solenoid member 34 through lead frame 57.
[0021] Electric power to the circuit board 50 is supplied through
connector member 60 (shown in FIGS. 1 and 2). The connector member
60 has a plurality of lead wires that are connected to the circuit
board. The lead wires include two wires which provide power to the
circuit board and a plurality of other wires which are signal wires
to provide signals to operate the electric motor and solenoid
member. The circuit board 50 is connected to the motor housing 22
by a plurality of fasteners, such as screw members 53.
[0022] Positioned between the circuit board 50 and the inside wall
of the motor housing is a gap filler member 55. The filler member
conducts heat from the circuit board into the aluminum motor
housing 22 where the heat in turn is distributed to the coolant
fluid which is being circulated in the impeller housing 30.
[0023] The gap filler member 55 can be any conventional type for
providing heat transfer between a CB heat source and a heat sink
surface. Gap fillers typically are soft materials with low
durometers and which have good thermal conductivity. Gap fillers
can be used to fill gaps between hot components. The materials can
be flexible with an elastic nature and can blanket uneven surfaces,
either individually or in layers or groups. In the present
invention, heat is conducted away from the circuit board 50 by the
gap filler 55 and into the aluminum motor housing 22 where the heat
is conducted to the cooler coolant fluid. Typically in vehicle
cooling systems, the coolant fluid has a maximum temperature of
about 129.degree. C., while most circuit board components have a
rated temperature of 150.degree. C. or higher.
[0024] The wall 72 of the motor housing 22 faces and is in contact
with the coolant fluid. The wall 72 has a plurality of fluid
recesses or pockets 70, and can be individual recesses or annular
grooves. Some of the recesses 70 are shown in FIG. 3. Any number of
recesses, pockets or grooves can be provided. These items 70 make
the motor housing wall 72 thinner in spots, places or areas, which
assists in transferring or conducting heat from the circuit board
50 and gap filler 55 into the coolant fluid. Preferably the
thickness of the motor housing wall in the bottoms of the recesses
is about five to twenty millimeters (5-20 mm) This is represented
by distance D in FIG. 3. The surfaces at the ends of the recesses,
pockets, grooves, etc. should be as thin as possible in order to
aid in transferring heat from the circuit board, but without
sacrificing the integrity and durability of the motor housing wall
72 or the motor housing itself.
[0025] The coolant pump shaft 28 is positioned centrally in the
housings 22 and 26, with the electric motor 24 and friction clutch
mechanism 33 being positioned in axial alignment around the shaft
28. An impeller member 80 is connected to impeller shaft 29 which
is connected at one end 28A of the coolant pump shaft 28. The
impeller member 80 and impeller shaft 29 protrude from the motor
housing and extend into the interior of the impeller housing
30.
[0026] The impeller housing 30 is made of a metal material, such as
aluminum, and has a central cavity 90, an inlet port 92 for inlet
of coolant fluid, and an outlet port (not shown) for passage of the
coolant fluid into the engine block 40. When the impeller 80 is
rotated by the dual mode coolant pump 20, the coolant liquid is
pumped through the outlet into and through the engine and the rest
of the engine cooling system, and then returned to the coolant pump
inlet port 92.
[0027] In an alternate embodiment of the invention, a coolant
control valve (CCV) can also be provided. Coolant control valves
control the direction and amount of flow of the coolant as it
enters the engine block.
[0028] As indicated above, the rotor 27 of the electric motor 24 is
fixedly attached to the coolant pump shaft 28 and rotates with it.
When the motor is activated, the shafts 28 and 29, as well as the
impeller member 80, rotate. The rotation of the impeller member
causes the coolant fluid to flow through the impeller housing and
the rest of the coolant system.
[0029] Preferably, the coolant pump shaft 28 is rotated by the
electric motor for most of the period in which a coolant pump is
needed. When additional coolant flow is required, such as when the
vehicle pulls a heavy load and more cooling is required, the pump
shaft 28 is rotated mechanically at input speed. For this purpose,
the solenoid member 34 is deenergized which allows armature member
110 to shift axially away from the solenoid. This allows the
friction lining member 112 on the spring biased friction plate 114
to contact the cover member 116. Since the cover member 116 is
attached to the pulley member 29 and rotates with it, this provides
rotation of the coolant pump shaft at input speed. The components,
including the solenoid member, armature member, friction plate,
friction linings and biasing spring members are collectively called
a friction clutch mechanism 33.
[0030] Under normal operation when the coolant pump shaft and
impeller are being rotated by the electric motor, the solenoid
member 34 is electrically activated. This attracts the armature
member 110, which is made of a magnetic metal material and prevents
the friction plate 114 from being biased against the cover where
the friction linings 112 on the friction plate 114 can contact the
inside surface of the cover member and cause mechanical rotation of
the shafts 28 and 29 and the impeller 80.
[0031] The coolant pump shaft 28 is mounted in the housing and
allowed to rotate by a pair of bearing members 120 and 122. The
electric rotor 27 is positioned on the shaft 28 between the two
bearing members 120, 122.
[0032] The pulley member 29 is mounted in the coolant pump by
bearing member 124 and allowed to rotate freely around the friction
clutch mechanism. The armature member 110 is biased in the coolant
pump by a plurality of coil spring members 130. Additional details
of the structure of the dual mode coolant pump and its operation
are contained in U.S. patent application Ser. No. 14/149,683, the
disclosure of which is incorporated herein by reference.
[0033] FIG. 4 depicts a preferred system and process for operating
the coolant pump 20 and a vehicle cooling system 130 in accordance
with the present invention. The coolant pump 20 is a dual mode
coolant pump and includes an electric motor 24, and a friction
clutch mechanism 33. The mechanism 33 in combination with a pulley
member 29 comprise a mechanical drive "M". The dual mode coolant
pump 20 rotates an impeller member 80 in the impeller housing
30.
[0034] The operation of the coolant pump 20 is operated by control
logic 140 which receives appropriate data and information from an
engine electronic control unit ("ECU") 142. The engine ECU 142
receives data and information from one or more temperature sensors
150, other engine and vehicle sensors 152, as well as control
instructions and signals from a vehicle ECU 160. The ECUs and
control logic operate the coolant pump 20 and impeller rotation to
maintain the temperature of the coolant fluid within acceptable
limits.
[0035] Coolant fluid from the coolant pump 20 flows into and
through the engine 40. The coolant fluid then exits the engine and
flows through a heat exchanger 184 such as a radiator, where it is
cooled. The temperature of the coolant can be read by a thermostat
190. Following flow through the heat exchanger, the cooler coolant
fluid is then returned 186 to the coolant pump 20.
[0036] The present invention provides an improved coolant pump and
engine cooling system that not only maintains the coolant fluid
within appropriate temperature limits, but also maintains the
temperature of the coolant pump electronics and circuit board
within their appropriate temperature limits. This provides a
coolant pump and cooling system which is efficient, durable, and
long-lasting.
[0037] Although the invention has been described with respect to
preferred embodiments, it is to be also understood that it is not
to be so limited since changes and modifications can be made
therein which are within the full scope of this invention as
detailed by the following claims.
* * * * *