Abstract:
In an electric motor-driven oil pump assembly for use with an engine in a vehicle, such as with an automatic engine-stop system in which an electric motor-driven oil pump is driven by an electric motor for hydraulic pressure supply to a transmission or engine of an automotive vehicle, at least in a stopped state of a mechanical oil pump driven by the engine, a controller for operating the motor for controlling the oil pump is provided in a housing proximal the flowing oil fluid such that the flowing oil fluid maintains the temperature of the controller below a predetermined temperature to avoid failure of the electronic components of the controller.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application is a U.S. National Phase of PCT/US2013/027874 filed Feb. 27, 2013 which claims the benefit of U.S. Provisional Patent Application No. 61/603,907 filed Feb. 27, 2012, each of which is incorporated herein by reference in its entirety. 
     
    
     FIELD 
       [0002]    The present disclosure relates generally to pumps for use in generating a flow of a fluid. More particularly, the present disclosure relates to an oil pump controlled by a controller for generating a fluid flow such as an oil pump for use in an engine in a vehicle. 
       BACKGROUND 
       [0003]    It is generally known that an oil pump is used to create a flow of fluid oil through an engine to cool and lubricate components of the drive train or engine during operation of the vehicle. It is also generally known to operate the oil pump using a power take off from the engine. In some applications, it is also generally known to provide an electric motor for operating the oil pump. Typically, it is also known to provide a controller including a circuit board and other electronic components for use in controlling the oil pump during operation of the vehicle. Most of the current applications have the controller integrated at the back of the motor housing where it is cooled only by the air flow. These applications are limited by maximum ambient temperature and the amount of power (i.e., current) that the system can draw before the electrical components of the controller overheat and shut down. 
         [0004]    So, if the electronic control apparatus is provided in the vehicle&#39;s power generation compartment, the temperature in the compartment generally creates a potential problem. While the air temperature in the compartment can be maintained at a sufficiently low temperature when a vehicle is moving and/or operating since fresh air flows can be used to transfer heat from the compartment, when the vehicle is stopped, such as after its high-speed running, the air stagnates in the compartment and is heated by the heat of the engine, with the result that the air temperature in the compartment rises to a relatively very high level which may lead to component fatigue, failure or other troubles. 
         [0005]    To obtain an electric motor which is both compact and capable of delivering high output torque, a large current must be passed through the coil of the motor proper and thus the controller must be capable of providing such high current to the motor. Passing a large current through the coil of the motor and the controller used to manage the supply of electrical energy to the motor can cause the motor and/or the controller to heat up and if heated too high, to eventually fail. Generally, it is required that the motor be cooled and that the controller be located at a distance from the motor and the heat source to protect the controller from extensive heat. Further, it is generally known to use very expensive components in the controller capable of functioning properly at such elevated temperatures. Accordingly, space must be provided to locate the controller and the motor to be able to function. However, it is very difficult to provide additional space for accommodating the installation of the electric motor and the controller because space is already very limited, particularly in the aforementioned motorized vehicle applications. Thus, it is very difficult to provide both the electric motor and the pump in a limited space. This has made it almost impossible and very expensive to implement such an electric-motor-driven pump. 
         [0006]    The present disclosure is based on the object of providing an electric motor-driven pump and control device by means of which the above-described problems of the prior art are avoided. 
       SUMMARY 
       [0007]    In one exemplary embodiment, there is disclosed an electronic motor-driven pump and integrated controller including a housing in which the controller, including power control components (e.g., MOSFETS) for supplying power to the motor, is arranged for controlling the rotational speed of a fluid pump and the output of the fluid pump to be supplied to a vehicle component. The electronic motor-driven pump includes a motor portion located at one end, the fluid pump in the middle and an inlet/outlet housing portion including an integrated portion for containing the controller and its components such that the integrated portion is located proximal the flowing fluid in the inlet and outlet and has sufficient thermal conductivity to sufficiently dissipate heat from the controller located in a cavity formed in the inlet/outlet housing portion. The inlet/outlet housing portion may also include one or more passages which extend parallel to the central axis of the pump and the motor for receipt of the wires required for electrically coupling the controller and the stator of the motor such that the wires also pass through a sealed passage extending axially through the fluid pump. Additionally, the fluid passes through the pump and the electric drive-motor to dissipate heat from all of the components of the assembly. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0008]    The drawings illustrate, by way of example only, embodiments of the present disclosure wherein: 
           [0009]      FIG. 1  is a perspective graphic view of an exemplary combined motor-driven pump and controller and housing system in accordance with the present disclosure; 
           [0010]      FIG. 2  is an exploded, perspective graphic view of the combined motor-driven pump and controller and housing system of the exemplary embodiment of  FIG. 1  in accordance with the present disclosure; 
           [0011]      FIG. 3  is a cross-section, graphic view of the combined motor-driven pump and controller and housing system of the exemplary embodiment of  FIG. 1  in accordance with the present disclosure; 
           [0012]      FIG. 4  is an exploded, perspective, graphic view of an alternative embodiment of a combined motor-driven pump and controller and housing system of the exemplary embodiment of  FIG. 1  in accordance with the present disclosure; 
           [0013]      FIG. 5  is a perspective, graphic view of a thermal image analysis for the combined motor-driven pump and controller and housing system of the exemplary embodiment of  FIG. 1  in accordance with the present disclosure; 
           [0014]      FIG. 6  is a perspective, graphic view of an alternate exemplary embodiment of a combined electric motor-driven pump, controller and housing system in accordance with the present disclosure showing the details of the innovation; 
           [0015]      FIG. 7  is a further alternate partial, perspective graphic view of the exemplary embodiment of  FIG. 6  with the controller cover and the controller removed showing the passages for routing the wires for the controller and the motor; 
           [0016]      FIG. 8  is a perspective, graphic view and a further alternate embodiment of a pump for inclusion in a combined motor-driven pump controller and housing system displaying an alternate side for coupling the pump housing to the motor for including the controller within the housing and affecting cooling thereof; 
           [0017]      FIG. 9  is a perspective, graphic view of a further alternate embodiment of a pump for inclusion in a combined motor-driven pump and controller and housing system similar to  FIG. 8  and showing an alternate oil inlet/outlet member; 
           [0018]      FIG. 10  is a cross-sectional, graphic view and the further alternate embodiment of a pump for inclusion in the motor-driven pump of the exemplary embodiment of  FIG. 9  in accordance with the present disclosure; 
           [0019]      FIG. 11  is a perspective, graphic view of a further alternate embodiment of a pump for inclusion in a combined motor-driven pump, controller and housing system similar to  FIG. 8  and showing an alternate oil inlet/outlet member; 
           [0020]      FIG. 12  is an exploded perspective, graphic view of the further alternate embodiment of a combined pump for inclusion in the motor-driven pump of the alternate exemplary embodiment of  FIG. 11  in accordance with the present disclosure and showing an intersecting vane embodiment according to the present disclosure; 
           [0021]      FIG. 13  is a perspective, graphic view of a further alternate embodiment of a pump for inclusion in the combined motor-driven pump and controller and housing system including an intersecting vane similar to  FIG. 12 ; 
           [0022]      FIG. 14  is a partial, perspective, graphic view of the further alternate embodiment of the pump for inclusion the combined motor-driven pump of the alternate exemplary embodiment of  FIG. 13  in accordance with the present disclosure; 
           [0023]      FIG. 15  is a perspective, graphic view of the further alternate embodiment of  FIG. 12  showing the detail of the variable displacement pump and the intersecting vane design; 
           [0024]      FIG. 16  is a partial, plan graphic view of the further alternate embodiment of  FIGS. 12 and 15  further showing the detail of the variable displacement pump and the intersecting vane design according to the present disclosure; and 
           [0025]      FIG. 17  is a diagrammatic view and exemplary boundary diagram of the combined motor-driven pump and controller and housing system according to the present disclosure. 
       
    
    
     DETAILED DESCRIPTION 
       [0026]    Referring in general to all of the figures, the present disclosure and teachings described herein provide for a combined motor-driven pump and controller system, hereinafter referred to as an electric motor-driven oil pump assembly  10 , for use in automotive applications such as in association with a vehicle engine or drive train, such as a transmission. The electric motor-driven oil pump assembly  10  provides lubrication, cooling and pressure in various system configurations. The primary elements of this electric motor-driven oil pump assembly  10  system are: the pump  20  which may be of any known or appropriate type (such as a fixed or variable displacement type pump), a motor  30 , in particular a brushless direct current (DC) type motor, and a motor controller  40 , such as a power inverter and an appropriate electrical connector for electrically coupling the electric motor-driven oil pump  10  to a source of electrical current power (such as a battery or similar type device). In addition, the electric motor-driven oil pump assembly  10  may also include known and/or appropriate diagnostics and sensor signals (not shown). The electric motor-driven oil pump assembly  10  is configured such that the whole assembly may be fully integrated (i.e., the pump  20 , motor  30 , controller  40  and electrical connector) and contained in a single, sealed (integrated) body  60  due to system restrictions such as packaging. However, in application, such a system is exposed to high ambient temperatures due to mounting locations and positions directly on the transmission or engine body (not shown) and even sometimes locations inside the transmission body. In these applications, the electric motor-driven oil pump assembly  10  is typically exposed to potentially very severe environments including elevated temperatures. The most sensitive component to high ambient temperatures is the motor controller  40  which has the effect of limiting the maximum operating temperature of the electric motor-driven oil pump assembly  10 . Currently, maximum operating temperatures for the motor controller subcomponents are as generally: 175 degrees Celsius for the FET junction, 150 degrees Celsius for the motor controller unit MCU and 135 degrees Celsius for the capacitor. 
         [0027]    To ensure that the noted temperature limits are not exceeded during maximum ambient temperature operation (Ta=138 degrees Celsius), the oil pump  20  uses oil flow to cool the controller  40 . Primarily, the benefit of the electric motor-driven oil pump assembly  10  according to the present disclosure is that it enables operation of the electric motor-driven oil pump assembly  10  under relatively higher ambient temperature conditions and at the same time provides for the possibility to reduce cost by using lower temperature grade electronic components as compared to known systems. As best shown in  FIG. 5 , pursuant to one set of exemplary operating conditions (i.e., ambient air at 138 degrees Celsius) the temperature of the oil flowing through the pump  20  keeps the oil at the inlet and at the outlet at 125 degrees Celsius which is below the noted temperature limits. Similarly, in  FIG. 6  the oil flows at 4.5 liters per minute (lpm) and the controller  40  is located in a first portion of an inlet/outlet housing  44  coupled to the oil pump assembly  20 . The first portion of the inlet/outlet housing  44  includes a first cavity  42  for receiving the controller  40  therein and having a cover  46  secured to the inlet/outlet housing for sealing the controller  40  and its components in the first cavity. The material of the inlet/outlet housing  44  is preferably chosen to have a relatively high thermal conductivity such as a metal, such as aluminum or an aluminum alloy or other known or appropriate materials. The first cavity  42  in the inlet/outlet housing  44  includes at least a first passage  45  extending from the first cavity  42  to the pump  20  and to a stator of the brushless direct current motor  30 . As best shown in the embodiment of  FIG. 4 , a bus-bar may be included in the motor assembly  30 , coupled to the stator, and including an extension for passing through a sealed passage extending through the pump  20  and into the passage of the inlet/outlet housing for being coupled and electrically connected with the controller  40  therein. 
         [0028]    As shown in the cross-section of  FIG. 3 , the controller  40  is located in the first cavity to be reasonably closely located proximate the inlet and outlet passages in the inlet/outlet housing  44  so that there is efficient heat transfer between the controller  40  and the fluid flowing therethrough. As the oil flows into the assembly  10 , it will have a relatively lower temperature than the heat produced by the motor  30  and will flow through the pump  20 , through the motor  30  and then back through the motor  30  and out of the inlet/outlet housing  44  where it will have a hydraulic pressure and flow to the vehicle component, such as a transmission or engine as well as, optionally, a heat exchanger where the oil may be cooled using any known or appropriate system and then returned to the assembly  10 . In the embodiments shown, it is possible for the motor  30  to be completely sealed such that the fluid flowing through the motor is completely sealed such that the fluid does not and cannot contact any of the electrical components of the motor  30  or of the controller  40 . A completely sealed assembly  10  is particularly significant and important for a fluid that may cause the electrical components to short, such as water. Alternatively, for a fluid that will not cause the electrical components to short, it is possible for the motor  30  and the controller  40  to be partially sealed or unsealed such that the fluid is allowed to contact the electrical components and thereby increase the heat transfer away from the electrical components. 
         [0029]    In an alternate embodiment shown in  FIGS. 8 through 14 , the pump  120  is shown having a controller  140  located at one side surface of the pump  120 . In particular, different types of pumps may be used such as the external rotor vane pump of  FIGS. 9 and 10  as well as the intersecting vane pump of  FIGS. 11 through 15  incorporating the teachings and disclosure of the present innovation. As should be understood from the present disclosure, it is possible to incorporate the teachings and disclosures of the present innovation into motor designs providing a variety of performance requirements and specifications including inter and out rotors, having between at least 12 Volts and 300 Volts applications. Further, it is possible to design the controller for providing a wide variety of design requirements such as FOC and Block, and 12V and 300V applications as well as including a variety of control strategies (i.e., control strategies based upon motor speed, torque, and current as well as based upon pump pressure). Accordingly, it should also be understood that the assembly  10  of the present disclosure provides for a variety of communication protocols to be utilized including but not limited to PWM, K-line, LINE, CAN or any other known or appropriate protocol. Accordingly, it is possible to provide an assembly  10  that is optimized to a significant variety of design specifications and preferences. 
         [0030]    In particular, it is contemplated that the assembly  10  according to the present disclosure, provides for a novel motor design for increasing the overall electric motor-driven pump performance while increasing the efficiency and reliability of the assembly  10  while reducing the costs of the components of the controller  40  and thereby the overall costs of the assembly  10 . 
         [0031]    Referring now in particular to the intersecting vane pump of  FIGS. 13 through 16  there is shown an oil pump  200 . The pump  200  includes a top plate, a motor, and a pump outer rotor and a pump inner rotor, as best shown in  FIGS. 15 and 16 . In particular, it should be understood that the outer pump rotor and the inner pump rotor both rotate with respect to the fixed bushing. Further of note is that the pump  200  includes first, second and third vanes (Vane 1, Vane 2, and Vane 3, respectively). Similar to the assembly  10  above, the pump  200  includes a controller (or PCB) coupled to a Base Plate and located under a Top (or Cover) Plate as best shown in  FIGS. 13 and 14 . The controller (PCB) is installed on the back side of the Base Plate so its heat will be dissipated by the fluid flowing from the Inlet Port to the Outlet Port. 
         [0032]    The internal components of the electric motor-driven oil pump  200  generally include the Motor Rotor, the Pump Outer Rotor, Vane 1, Vane 2, Vane 3, the Pump Inner Rotor and the Bushing all coupled together as shown. The Inlet Port and Outlet Port are located in the Base Plate and are coupled to the pump  200  for flowing the fluid through the pump using the intersecting vane design as shown. 
         [0033]    The Pump Outer Rotor is preferably pressed into the Motor Rotor. The Pump Outer Rotor includes at a first location a half circle or scallop on the inner bore of the Pump Outer Rotor for receiving a first end of Vane 1. Vane 1 extends from the scallop in the inner bore of the Pump Outer Rotor and through a first slot located transversely across the Pump Inner Rotor. Vane 2 and Vane 3 are installed in second and third slots of the Pump Inner Rotor and are each guided by the shaped contour of the inner circumference of the bore or passage of the Pump Outer Rotor. The contour of the inner circumference of the bore or passage of the Pump. Outer Rotor is shaped to affect the operation of the Vanes 1, 2, and 3 during rotation of the rotors for the pump  200  to perform consistent with desired design requirements. When the motor  200  is working, the Motor Rotor and Pump Outer Rotor will rotate in a clockwise direction as shown in  FIG. 15 , and will drive Vane 1 and the Pump Inner Rotor and then will drive Vane 2 and Vane 3 but, the three Vanes will only swing back and forth during some angles related to the Pump Rotor to move fluid through the pump  200  causing oil to flow from the Inlet Port through the pump to the outlet port. 
         [0034]    The configuration of the pump  200  according to the present disclosure is selected so the Pump Outer Rotor is a driving member and the Inner Rotor is driven by Vane 1 connected with Pump Outer Rotor. This type of pump driving method and configuration is unique so the contour of the inner circumference of the bore or passage of the Pump Outer Rotor is a pre-selected curve so that when the Pump Outer Rotor is rotated, the three Vanes 1, 2, and 3 will only swing back and forth during some angles related to the Pump Rotor. 
         [0035]    The pump  200  of the present disclosure particularly benefits from the current design because the electric motor-driven oil pump  200  may work at high ambient temperature conditions while at the same time providing the possibility for significantly reduced cost by using lower temperature grade electronic components in the controller (PCB) as well as a reduced number of mechanical components making up the pump  200  as compared to conventional vane pumps thereby further reducing cost. 
         [0036]    Any numerical values recited herein or in the figures are intended to include all values from the lower value to the upper value in increments of one unit provided that there is a separation of at least 2 units between any lower value and any higher value. As an example, if it is stated that the amount of a component or a value of a process variable such as, for example, temperature, pressure, time and the like is, for example, from 1 to 90, preferably from 20 to 80, more preferably from 30 to 70, it is intended that values such as 15 to 85, 22 to 68, 43 to 51, 30 to 32 etc. are expressly enumerated in this specification. For values which are less than one, one unit is considered to be 0.0001, 0.001, 0.01 or 0.1 as appropriate. These are only examples of what is specifically intended and all possible combinations of numerical values between the lowest value and the highest value enumerated are to be considered to be expressly stated in this application in a similar manner. As can be seen, the teaching of amounts expressed as “parts by weight” herein also contemplates the same ranges expressed in terms of percent by weight. Thus, an expression in the Detailed Description of the Invention of a range in terms of at “‘x’ parts by weight of the resulting polymeric blend composition” also contemplates a teaching of ranges of same recited amount of “‘x’ in percent by weight of the resulting polymeric blend composition.” 
         [0037]    Unless otherwise stated, all ranges include both endpoints and all numbers between the endpoints. The use of “about” or “approximately” in connection with a range applies to both ends of the range. Thus, “about 20 to 30” is intended to cover “about 20 to about 30”, inclusive of at least the specified endpoints. 
         [0038]    The disclosures of all articles and references, including patent applications and publications, are incorporated by reference for all purposes. The term “consisting essentially of” to describe a combination shall include the elements, ingredients, components or steps identified, and such other elements, ingredients, components or steps that do not materially affect the basic and novel characteristics of the combination. The use of the terms “comprising” or “including” to describe combinations of elements, ingredients, components or steps herein also contemplates embodiments that consist essentially of the elements, ingredients, components or steps. By use of the term “may” herein, it is intended that any described attributes that “may” be included are optional. 
         [0039]    Plural elements, ingredients, components or steps can be provided by a single integrated element, ingredient, component or step. Alternatively, a single integrated element, ingredient, component or step might be divided into separate plural elements, ingredients, components or steps. The disclosure of “a” or “one” to describe an element, ingredient, component or step is not intended to foreclose additional elements, ingredients, components or steps. 
         [0040]    It is understood that the above description is intended to be illustrative and not restrictive. Many embodiments as well as many applications besides the examples provided will be apparent to those of skill in the art upon reading the above description. The scope of the invention should, therefore, be determined not with reference to the above description, but should instead be determined with reference to the appended claims, along with the full scope of equivalents to which such claims are entitled. The disclosures of all articles and references, including patent applications and publications, are incorporated by reference for all purposes. The omission in the following claims of any aspect of subject matter that is disclosed herein is not a disclaimer of such subject matter, nor should it be regarded that the inventors did not consider such subject matter to be part of the disclosed inventive subject matter.