Patent Application
20240068481
This disclosure is generally directed to a multiport fluid pump for switching flow to heat generating or absorbing components. More specifically to a multiport fluid pump with integrated valve that has a reserve capacity impeller.
Pumps are known and commonly used to move fluids, such as coolant in a vehicle. One example is cooling systems with water pumps, which are used for the cooling of different electrical or mechanical components of a vehicle. In hybrid or purely electric vehicles, electrical components need to be cooled. Valves are used to ensure the distribution of the coolant throughout the cooling system. The valves each require an actuator with electrical control and a holder on a component of the vehicle, which results in high component costs. In some vehicles, more than one cooling loop may be employed to cool heat generating components and to modulate the temperature of the driver cabin. In pumps having multiple output ports that connect a single pump to one or more cooling loops a valve may be used to switch and direct the fluid flow between the one or more cooling loops. Rotating impellers driven by electric motors or by other mechanical means are used by the pump to drive coolant fluid from the pump through the one or more cooling loops. The impeller, housing and outlet ports of the pump are designed to provide a rate of fluid flow based on the rotation of the impeller with a maximum degree of efficiency and a minimum degree of flow restriction. It would be desirable to provide an impeller with reserve capacity to provide the same rate fluid flow through two or more cooling loops as it does to a single cooling loop.
This disclosure relates to an apparatus for distributing coolant fluid through first and second coolant loops comprising a pump having a housing including an inlet port connected to a source of coolant fluid and a first outlet port connected to the first coolant loop and a second outlet port connected to the second coolant loop. A valve located in the pump housing is switchable to direct coolant fluid from the inlet port to either the first or the second outlet port individually or to the first and second outlet ports concurrently. An impeller located in the pump housing pumps the coolant fluid received from the inlet port at an unrestricted rate of flow. The coolant fluid is circulated through the first coolant loop at a rate of flow less than the unrestricted rate of flow when the valve connects the first outlet port to the first coolant loop and circulated through the second coolant loop at a rate of flow less than the unrestricted rate of flow when the valve connects the second outlet port to the second coolant loop. The coolant fluid is circulated through the first and the second coolant loops at a rate of flow less than the unrestricted rate of flow when the valve connects the first and the second outlet ports concurrently to the first and second coolant loops and which the rates of flow through the first and the second coolant loops jointly equal the unrestricted rate of flow.
This disclosure also relates to a process for distributing coolant fluid through first and second coolant loops comprising pumping coolant fluid from a pump at an unrestricted rate of flow and positioning a valve into a first position to direct the coolant fluid through a first outlet port of the pump connected to the first coolant loop causing the coolant fluid to circulate through the first coolant loop at a rate of flow less than the unrestricted rate of flow. The process further comprises positioning the valve into a second position to direct the coolant fluid through a second outlet port of the pump connected to the second coolant loop, causing the coolant fluid to circulate the coolant fluid through the second coolant loop at a rate of flow less than the unrestricted rate of flow. The process further comprise positioning the valve into a third position to direct the coolant fluid through the first and the second outlet ports concurrently causing the coolant fluid to circulate through each of the first and the second coolant loops at a rate of flow less than the unrestricted rate of flow and that jointly equals the unrestricted rate of flow.
Other technical features may be readily apparent to one skilled in the art from the following figures, descriptions, and claims.
For a more complete understanding of this disclosure, reference is now made to the following description, taken in conjunction with the accompanying drawings, in which:
The figures, discussed below, and the various embodiments used to describe the principles of the present invention in this patent document are by way of illustration only and should not be construed in any way to limit the scope of the invention. Those skilled in the art will understand that the principles of the invention may be implemented in any type of suitably arranged device or system.
The first coolant loop 30 containing a coolant fluid is fluidically connected to a heat dissipating device 12 such as for example, a heat exchanger or a radiator that uses an electrically or mechanically driven fan to provide the transfer of heat from the coolant by directing air at an ambient temperature over the heat dissipating device 12. The heat dissipating device 12 removes the heat absorbed by the coolant fluid from the heat generating components. A second coolant loop 40 containing coolant fluid fluidically connects the energy generating components 14, 16 to the heat dissipating device 12 through junction 18. The first and second loops 30 and 40 are both connected to an electrically driven pump 50. The pump 50 includes a suction inlet port 51 fluidically connected to fluid line 16 from the heat dissipating device 12. The inlet port 51 receives the coolant fluid from the heat dissipating device 12 and pumps the coolant fluid through loops 30 and 40. The pump 50 further includes two outlet ports 55 and 58. Outlet port 55 provides a fluid outlet from the pump 50 to fluid line 21 of coolant loop 30 and outlet port 58 provides a separate fluid outlet to fluid line 23 of coolant loop 40. A valve 56 installed is installed in pump 50 is movable to switch the flow of coolant fluid from the outlet ports.
For example, in
In
In
It is a practiced art in pump design to define a rate of flow that a pump can produce at a setpoint RPM produced by the motor driving the pump. The geometric design of pump impeller and the outlet port housing/volute area work in conjunction with the setpoint RPM to achieve a desired rate of flow from the pump without flow restriction. Flow restriction causes an inefficient use of the energy due to the impeller spinning throttled fluid that does not exit the pump. An oversized impeller used within a restricted pump housing or with an outlet port having a small diameter or outlet area results in a geometric restriction and a throttled rate of flow.
For example, if the interior housing volume of the pump housing and of the outlet ports surrounding an impeller are too small for a setpoint RPM, the rate of flow at a setpoint RPM will be restricted and the full rate of flow that the impeller has the capacity to produce will not exit the outlet. The solution to such a restriction in flow would be to increase the housing volume or reduce the impeller geometry, such as for example the impeller outside diameter to provide a more efficient rate of flow.
However, an impeller design that lends itself to a non-restricted and efficient rate of flow for a one outlet pump, does not provide a sufficient rate of flow in a switched multiport pump when two or more outlet ports are open in the pump. A pump design having an impeller optimally designed to provide an efficient rate of flow for a pump having one outlet port would produce a fractional rate of flow for a pump having two or more open outlet ports.
For example, sizing the impeller to have twice the capacity as allowed by outlet volume formed by the housing and a single outlet port opening results in a restricted or throttled impeller capacity (φrestriction=Restriction Factor). In this example, the inlet flow rate is half the impeller flow capacity (φrestriction=2 or Qimpeller/2). Likewise, the outlet rate of flow, less any minor losses, trails the inlet flow and is also half the impeller capacity (Qimpeller/2). The factor of 2 is shown for convenience only.
Q
impeller=Impeller Capacity
Q
inlet
=Q
impeller/φrestriction
Q
youtlet
=Q
impeller/φrestriction
For a pump that has multiple switched outlet ports it is advantageous to oversize the impeller for a single outlet port setpoint RPM, in order to provide an equal amount of a rate of flow when two or more outlet ports are open. For example, using an impeller that has twice the capacity as allowed by outlet volume formed by the housing and a single outlet port results in a restricted or throttled impeller capacity as shown above. However, when the switched pump opens two or more outlet ports the impeller capacity is no longer throttled. This results in the full unrestricted impeller capacity to be realized at the same setpoint RPM. The inlet capacity increases to match the outlet capacity (Qinlet=Qimpeller The resulting outlet rate of flow to both open outlet ports follows the impeller capacity divided by the number of outlets (noutlets) or (Qx-outlet=Qimpeller/noutlets and Qy-outlet=Qimpeller/noutlets). For convenience two outlets are shown for this example (noutlets=2). Where:
Q
impeller=Impeller Capacity
Q
inlet
=Q
impeller
Q
x-outlet
=Q
impeller
/n
outlets
Q
y-outlet
=Q
impeller
/n
outlets
This results in the full unrestricted impeller capacity to be used at the same setpoint RPM and where the inlet capacity equals the impeller capacity. Therefore, it is advantageous in a switched pump to design the impeller to be restricted when only one outlet port is open in order to provide a reserve capacity when two or more outlet ports are open.
In
Referring to
In operation, rotation of the valve member 142 selectively switch opening 144 to divert coolant fluid from the pump cavity 150 to the first outlet port 55, to the second outlet port 58 or to both outlet ports 55, 58 concurrently, thereby controlling the discharge of coolant fluid from the pump section 104.
As was explained above the impeller 116 is designed to have twice the capacity as allowed by outlet volume formed by the housing and each single port opening of outlets 55, 58. This results in a restricted or throttled impeller capacity (φrestriction=Restriction Factor). In the example explained earlier, the inlet flow rate is half the impeller flow capacity (φrestriction=2 or Qimpeller/2). Likewise, the outlet flow, less any minor losses, trails the inlet flow and is also half the impeller capacity (Qimpeller/2). For example, the impeller 116 is designed to provide a 100 liters per minute (Ipm) of a rate of flow at a setpoint of 5000 RPM. This is the maximum efficient flow rate for the impeller 116. However, as explained earlier, the pump 50 throttles or restricts flow rate when only one of the two available outlet ports is switched into operation. Switching the valve member 56 in either the first or the second position the rate of flow is throttled achieving a rate of flow of 50 liters per minute (Ipm), or approximately half of its designed rate of flow from any one of the fluid outlets 55, 58 (Qx-outlet or Qy-outlet).
Wrpmsetpoint=5000rpm
Qimpeller=100 lpm
Qinlet=50 lpm
Qx-outlet or Qy-outlet=50 lpm
The impeller 116 has the capacity to produce a rate of flow of 100 lpm, however when only one of the two fluid outlets is open, a throttled rate of flow of 50 lpm is output from any one of the individually open fluid outlet 55, 58 and therefore the impeller 116 has a reserve capacity of 50 lpm.
Switching the valve 56 by the actuator into the third position is shown in
Wrpmsetpoint=5000rpm
Qimpeller=100lpm
Qinlet=100lpm
Qx-outlet and Qy-outlet=50lpm
Thereby using the reserve capacity to provide an equal rate of flow through each of the loops 30 and 40.
It will be appreciated by those skilled in the art that an impeller 116 can be designed to provide a reserve capacity impeller to maintain an equal rate of flow from pumps having three or more switched outlet ports at a setpoint RPM. For example, when the pump impeller is sized by design to have a rate of flow that is unrestricted or not-throttled by the housing, volute volume and fluid outlet in a dual flow mode, e.g. a first and a second outlet port open of a three outlet port pump, the simultaneous rate of flow is the sum of both rates of flow from the two open outlet ports, which will be equal to the rate of flow at the pump inlet port, which is in turn, is equal to the impeller flow capacity at the rpm setpoint. When the valve of the pump is switched to only one open port, e.g., third outlet port open and the first and second outlet ports closed, the rate of flow will be a flow rate that is equal to the rate of flow through either of the two previously open outlet ports with the inlet being half of the impeller capacity.
It may be advantageous to set forth definitions of certain words and phrases used throughout this patent document. The term “communicate,” as well as derivatives thereof, encompasses both direct and indirect communication. The terms “include” and “comprise,” as well as derivatives thereof, mean inclusion without limitation. The term “or” is inclusive, meaning and/or. The phrase “associated with,” as well as derivatives thereof, may mean to include, be included within, interconnect with, contain, be contained within, connect to or with, couple to or with, be communicable with, cooperate with, interleave, juxtapose, be proximate to, be bound to or with, have, have a property of, have a relationship to or with, or the like. The phrase “at least one of,” when used with a list of items, means that different combinations of one or more of the listed items may be used, and only one item in the list may be needed. For example, “at least one of: A, B, and C” includes any of the following combinations: A, B, C, A and B, A and C, B and C, and A and B and C.
The description in the present application should not be read as implying that any particular element, step, or function is an essential or critical element that must be included in the claim scope. The scope of patented subject matter is defined only by the allowed claims. Moreover, none of the claims is intended to invoke 35 U.S.C. § 112(f) with respect to any of the appended claims or claim elements unless the exact words “means for” or “step for” are explicitly used in the particular claim, followed by a participle phrase identifying a function. Use of terms such as (but not limited to) “mechanism,” “module,” “device,” “unit,” “component,” “element,” “member,” “apparatus,” “machine,” “system,” or “controller” within a claim is understood and intended to refer to structures known to those skilled in the relevant art, as further modified or enhanced by the features of the claims themselves and is not intended to invoke 35 U.S.C. § 112(f).
While this disclosure has described certain embodiments and generally associated methods, alterations and permutations of these embodiments and methods will be apparent to those skilled in the art. Accordingly, the above description of example embodiments does not define or constrain this disclosure. Other changes, substitutions, and alterations are also possible without departing from the spirit and scope of this disclosure, as defined by the following claims.
