Some example embodiments relate to circulating devices, and at least some example embodiments relate specifically to variable control intelligent pumps.
Pumps can be used in a variety of applications, including industrial processes, meaning a process that outputs product(s) (e.g. hot water, air) using inputs (e.g. cold water, fuel, air, etc.), Heating, ventilation and air conditioning (HVAC) systems, and water supply.
Some pump units are designed with two pumps in one unit, sometimes referred to as twin heads or dual heads. In some such units, the two pumps are designed to rotate in the same rotational direction. However, this can result in asymmetry in physical design and asymmetry in flow profiles.
Some pump systems require a keypad or keyboard input for setup, configuration and maintenance, which can be prone to sealing problems. Some other pump systems may require a separate mobile handheld device for setup, configuration and maintenance.
Additional difficulties with existing systems may be appreciated in view of the Detailed Description of Example Embodiments, herein below.
Example embodiments relate to pumps, boosters and fans, centrifugal machines, and related systems. In accordance with some aspects, there is provided an intelligent multiple circulating pump unit having multiple pumps and with co-ordinated control of its pumps.
An example embodiment includes a dual pump unit having a pair of pumps that provide parallel hydraulic paths that operate concurrently in opposite rotational directions.
An example embodiment is a pump unit, including: a casing including a suction flange and a discharge flange; a first pump impeller within the casing; a second pump impeller within the casing and provides a parallel hydraulic path to the first pump impeller; wherein the first pump impeller is configured to concurrently rotate in opposite rotational direction to the second pump impeller.
Another example embodiment is a pump unit, including: a casing including a suction flange and a discharge flange; a first pump within the casing; a second pump within the casing and provides a parallel hydraulic path to the first pump impeller; a first touchscreen mounted on the casing for input and/or output in association with the first pump; and a second touchscreen mounted on the casing for input and/or output in association with the second pump.
Another example embodiment is a pump unit casing, including: a casing including a suction flange and a discharge flange; and a suction bay defined by the casing having a flattened bottom and hydraulically fed from the suction flange.
Another example embodiment is a method for operating a multiple pump unit, the pump unit including a casing including a suction flange and a discharge flange, a first pump impeller within the casing, and a second pump impeller within the casing and provides a parallel hydraulic path to the first pump impeller. The method includes: rotating the first pump impeller in a rotation direction to effect flow between the suction flange and the discharge flange; and concurrently rotating the second pump impeller in a counter rotation direction to effect flow between the suction flange and the discharge flange.
Another example embodiment is an integrated pump unit, including: a casing; a pump within the casing; a controller for controlling operation of the pump; and a touchscreen configured for input and/or output communication to the controller.
Another example embodiment is a non-transitory computer readable medium having instructions stored thereon executable by one or more processors for performing the described methods.
Embodiments will now be described, by way of example only, with reference to the attached Figures, wherein:
Like reference numerals may be used throughout the Figures to denote similar elements and features.
In some example embodiments, there is provided an intelligent multiple pump unit for an operable system such as a flow control system or temperature control system. Example embodiments relate to “processes” in the industrial sense, meaning a process that outputs product(s) (e.g. hot water, air) using inputs (e.g. cold water, fuel, air, etc.).
An example embodiment includes a dual pump unit having a pair of pumps that provide parallel hydraulic paths that operate concurrently in opposite rotational directions.
An example embodiment includes a dual pump unit having a casing which includes a suction flange and a discharge flange, and a pair of pumps that are radially inline and that provide parallel hydraulic paths within the casing, that operate concurrently in opposite rotational directions.
An example embodiment includes a dual pump unit having a pair of pumps that provide parallel hydraulic paths, wherein each pump includes a touchscreen for configuration of the respective pump.
An example embodiment includes a pump unit casing having a suction flange and a discharge flange, a first suction bay defined by the casing having a first flattened bottom and hydraulically fed from the suction flange, and a second suction bay defined by the casing having a second flattened bottom and hydraulically fed from the suction flange and provides a parallel hydraulic path to the first suction bay.
An example embodiment includes a dual pump unit which controls operation of a plurality of its sensorless pumps in a co-ordinated manner. For example, in some embodiments the system may be configured to operate without external sensors to collectively control output properties (variables) to source a load.
Reference is made to
As illustrated in
The control device 108 for each control pump 102 may include an internal detector or sensor, typically referred to in the art as a “sensorless” control pump because an external sensor is not required. The internal detector may be configured to self-detect, for example, device properties (device variables) such as the power and speed of the pump device 106. In some example embodiments, an external sensor is used to detect the local head output and flow output (H, F). Other input variables may be detected. The pump speed of the pump device 106 may be varied to achieve a pressure and flow setpoint of the pump device 106 in dependence of the input variables.
Referring still to
One or more controllers 116 (e.g. processors) may be used to co-ordinate the output flow of the control pumps 102. As shown, the control pumps 102 may be arranged in parallel with respect to the flow path in order to source shared loads 110a, 110b, 110c, 110d.
In some examples, the circulating system 100 may be a chilled circulating system (“chiller plant”). The chiller plant may include an interface 118 in thermal communication with a secondary circulating system for the building 104. The control valves 112a, 112b, 112c, 112d manage the flow rate to the cooling coils (e.g., load 110a, 110b, 110c, 110d). Each 2-way valve 112a, 112b, 112c, 112d may be used to manage the flow rate to each respective load 110a, 110b, 110c, 110d. As a valve 112a, 112b, 112c, 112d opens, the differential pressure across the valve decreases. The control device 108 responds to this change by increasing the pump speed of the pump device 106 to achieve a specified output setpoint. If a control valve 112a, 112b, 112c, 112d closes, the differential pressure across the valve increases, and the control devices 108 respond to this change by decreasing the pump speed of the pump device 106 to achieve a specified output setpoint.
In some other examples, the circulating system 100 may be a heating circulating system (“heating plant”). The heater plant may include an interface 118 in thermal communication with a secondary circulating system for the building 104. In such examples, the control valves 112a, 112b, 112c, 112d manage the flow rate to heating elements (e.g., load 110a, 110b, 110c, 110d). The control devices 108 respond to changes in the heating elements by increasing or decreasing the pump speed of the pump device 106 to achieve the specified output setpoint.
Each pump device 106 may take on various forms of pumps which have variable speed control.
The intelligent dual pump unit 101 includes a sealed casing which houses the pump device 106, which includes a suction flange 124 for connecting to a line for receiving a circulating medium, and a discharge flange 126 for connecting to a line for outputting of the circulating medium. Each control pump 102a, 102b includes a respective suction bay 128a, 128b. A respective volute 130a, 130b fed from the respective suction bay 128a, 128b is used for housing of the respective pump impeller 122a, 122b. A respective variable motor, not shown here, can be variably controlled from the control device 108a, 108b to rotate at variable speeds. Each control pump 102a, 102b may further include a respective touchscreen 120a, 12b for interaction, input and/or output, between the user and the respective control device 108a, 108b. The pump impeller 122a, 122b is operably coupled to the motor and spins based on the speed of the motor, to circulate the circulating medium. In an example embodiment, the first control device 108a and the second control device 108b are configured to control the respective pump impeller 122a, 122b in a range of 0% to 100% of motor speed. The control of both pumps 122a, 122b can be performed symmetrically or asymmetrically. In other example embodiments, other suitable ranges can be a range narrower than between 0% to 100%, depending on desired or system operation ranges.
Each control pump 102a, 102b may further include additional suitable operable elements or features, depending on the type of pump device 106. Each volute 130a, 130b can be configured to receives the circulating medium being pumped by the respective pump impeller 122a, 122b, slowing down the fluid's rate of flow. Each volute 130a, 130b can comprise a curved funnel that increases in area as it approaches the discharge flange 126.
In an example embodiment, the casing of the pump unit 101 is substantially symmetrical in shape and dimension. This facilitates ease of design and manufacturing. This also facilitates balance in operation and centralizing the centre of gravity. Further, for example, each of the control pumps 102a, 102b can be controlled to operate concurrently. The pump impellers 122a, 122b are co-ordinated so that combined output achieves a setpoint. In an example embodiment, the control pumps 102a, 102b are controlled at the same motor speed. When the casing is substantially symmetrical, then same motor speeds results in substantially equal contribution effected onto the circulating medium by each of the control pumps 102a, 102b.
A flap valve 140 of the pump unit 101 will now be described, referring to
The flap valve 140 includes a spring hinge 142, a first flap 144a and a second flap 144b connected to the spring hinge. The spring hinge 142 is configured and biased so that each flap 144a, 144b is normally closed, as in
In an example embodiment, the pump impellers 122a, 122b are controlled to rotate concurrently at different speeds. In an example embodiment, the pump impellers 122a, 122b are controlled to rotate at less than the maximum motor capacity (speed). As variable motors can have optimal efficiency at less than maximum speed, energy efficiencies may be gained in some example implementations. In an example embodiment, the pump impellers 122a, 122b may be controlled to distribute wear between the respective control pumps 102a, 102b. For example, if one control pump 102a is inactive for a duration, the subsequent use of that control pump 102a can be increased so that the wear is distributed. In an example embodiment, the control devices 108a, 108b are further configured to operate the pump impellers 122a, 122b as duty-standby, in another mode of operation. For example, in such a mode, one primary pump 108a may designated as the primary pump source (“duty”), while a secondary pump can be used as backup (“standby”) when the primary pump is not available.
Reference is now briefly made to
Still referring to
Reference is now made to
At event 1502, the method 1500 includes determining the desired output setpoint, for example the pressure setpoint of the system 100 (
At event 1504, the method 1500 includes detecting inputs including variable such as system variables or device variables of each device (e.g., each control pump 102a, 102b). At event 1506, the method 800 includes determining the one or more output properties (output variables) of each device. This can be directly detected or inferred from the device properties (device variables). The respective one or more output properties can be calculated to determine the individual contributions of each device to the system load point. At event 1508, the method 1500 includes determining the aggregate output properties (output variables) to the load from the individual one or more output properties. At event 1510, the method includes co-ordinating control of each of the devices to operate the respective controllable element (e.g. pump impeller 122a, 122b), resulting in one or more device variables to achieve the respective one or more output properties to achieve the setpoint. This includes rotating the first pump impeller 122a in a rotation direction to effect flow between the suction flange and the discharge flange, and concurrently rotating the second pump impeller 122b in a counter rotation direction to effect flow between the suction flange and the discharge flange. The method 1500 may be repeated, for example, as indicated by the feedback loop.
In an example embodiment, the pump impellers 122a, 122b are controllable to concurrently rotate at an equal speed. Due to the symmetrical casing of the pump unit 101, equal motor speed results in equal flow output contribution by each of the pump impellers 122a, 122b. The hydraulic characteristics of the casing and each pump impeller 122a, 122b therefore provide hydraulically identical net flow and head pressure upon identical speed rotation of each pump impeller 122a, 122b. Equal and opposite flow paths result from each pump impeller 122a, 122b in such a case. In an example embodiment, the pump impellers 122a, 122b are controllable to concurrently rotate at different speeds. In an example embodiment, the pump impellers 122a, 122b are controllable to rotate at less than maximum speed of each respective pump motor.
Reference is now made to
The design point, Point A (210), can be estimated by the system designer based on the flow that will be required by a system for effective operation and the head/pressure loss required to pump the design flow through the system piping and fittings. Note that, as pump head estimates may be over-estimated, most systems will never reach the design pressure and will exceed the design flow and power. Other systems, where designers have under-estimated the required head, will operate at a higher pressure than the design point. For such a circumstance, one feature of properly selecting one or more intelligent variable speed pumps is that it can be properly adjusted to delivery more flow and head in the system than the designer specified.
The design point can also be estimated for operation with multiple controlled pumps 102, with the resulting flow requirements allocated between the controlled pumps 102. For example, for controlled pumps of equivalent type or performance, the total estimated required output properties 114 (e.g. the maximum flow to maintain a required pressure design point at that location of the load) of a system or building 104 may be divided equally between each controlled pump 102 to determine the individual design points, and to account for losses or any non-linear combined flow output. In other example embodiments, the total output properties (e.g. at least flow) may be divided unequally, depending on the particular flow capacities of each control pump 102, and to account for losses or any non-linear combined flow output. The individual design setpoint, as in point A (210), is thus determined for each individual control pump 102.
The graph 200 includes axes which include parameters which are correlated. For example, head squared is approximately proportional to flow, and flow is approximately proportional to speed. In the example shown, the abscissa or x-axis 204 illustrates flow in U.S. gallons per minute (GPM) (can be litres per minute) and the ordinate or y-axis 206 illustrates head (H) in pounds per square inch (psi) (alternatively in feet/meters or Pascals). The range of operation 202 is a superimposed representation of the control pump 102 with respect to those parameters, onto the graph 200.
The relationship between parameters may be approximated by particular affinity laws, which may be affected by volume, pressure, and Brake Horsepower (BHP) (e.g. in kilowatts). For example, for variations in impeller diameter, at constant speed: D1/D2=Q1/Q2; H1/H2=D12/D22; BHP1/BHP2=D13/D23. For example, for variations in speed, with constant impeller diameter: S1/S2=Q1/Q2; H1/H2=S12/S22; BHP1/BHP2=S13/S23. Wherein: D=Impeller Diameter (Ins/mm); H=Pump Head (Ft/m); Q=Pump Capacity (gpm/lps); S=Speed (rpm/rps); BHP=Brake Horsepower (Shaft Power—hp/kW).
Specifically, for the graph 200 at least some of the parameters there is more than one operation point or path of system variables of the operable system that can provide a given output setpoint. As is understood in the art, at least one system variable at an operation point or path restricts operation of another system variable at the operation point or path.
Also illustrated is a best efficiency point (BEP) curve 220 of the control pump 102. The partial efficiency curves are also illustrated, for example the 77% efficiency curve 238. In some example embodiments, an upper boundary of the range of operation 202 may also be further defined by a motor power curve 236 (e.g. maximum Watts or horsepower). In alternate embodiments, the boundary of the range of operation 202 may also be dependent on a pump speed curve 234 (shown in Hz) rather than a strict maximum motor power curve 236.
As shown in
Other example control curves other than quadratic curves include constant pressure control and proportional pressure control (sometimes referred to as straight-line control). Selection may also be made to another specified control curve (not shown), which may be either pre-determined or calculated in real-time, depending on the particular application.
Referring again to
The input subsystems 522a can receive input variables. Input variables can include, for example, sensor information or information from the device detector 304 (
The communications subsystem 516a is configured to communicate with, either directly or indirectly, the other controller 116 and/or the second control device 108b. The communications subsystem 516a may further be configured for wireless communication. The communications subsystem 516a may further be configured for direct communication with other devices, which can be wired and/or wireless. An example short-range communication is Bluetooth® or direct Wi-Fi. The communications subsystem 516a may be configured to communicate over a network such as a wireless Local Area Network (WLAN), wireless (Wi-Fi) network, public land mobile network (PLMN), and/or the Internet. These communications can be used to co-ordinate the operation of the control pumps 102 (
The memory 508a may also store other data, such as the load profile 400 (
One type of conventional pump device estimates the local flow and/or pressure from the electrical variables provided by the electronic variable speed drive. This technology is typically referred to in the art as “sensorless pumps” or “observable pumps”. Example implementations using a single pump are described in WO 2005/064167, U.S. Pat. Nos. 7,945,411, 6,592,340 and DE19618462, herein incorporated by reference. The single device can then be controlled, but using the estimated local pressure and flow to then infer the remote pressure, instead of direct fluid measurements. This method saves the cost of sensors and their wiring and installation, however, these references may be limited to the use of a single pump.
In an example embodiment, the intelligent dual pump unit 101 can be configured to operate both pumps 102a, 102b using at least one internal sensor without necessarily requiring an external sensor, e.g., in a “sensorless” manner. An example of a co-ordinated sensorless system is described in Applicant's PCT Patent Application Publication No. WO 2014/089693 filed Nov. 13, 2013, entitled CO-ORDINATED SENSORLESS CONTROL SYSTEM, herein incorporated by reference.
Reference is now made to
Note that the internal detector 304 for self-detecting device properties (device variables) contrasts with some systems which may use a local pressure sensor and flow meter which merely directly measures the pressure and flow across the control pump 102. Such variables (local pressure sensor and flow meter) may not be considered device properties (device variables), in example embodiments.
Another example embodiment of a variable speed sensorless device is a compressor which estimates refrigerant flow and lift from the electrical variables provided by the electronic variable speed drive. In an example embodiment, a “sensorless” control system may be used for one or more cooling devices in a controlled system, for example as part of a “chiller plant” or other cooling system. For example, the variable speed device may be a cooling device including a controllable variable speed compressor. In some example embodiments, the self-detecting device properties of the cooling device may include, for example, power and/or speed of the compressor. The resultant output properties may include, for example, variables such as temperature, humidity, flow, lift and/or pressure.
Another example embodiment of a variable speed sensorless device is a fan which estimates air flow and the pressure it produces from the electrical variables provided by the electronic variable speed drive.
Another example embodiment of a sensorless device is a belt conveyor which estimates its speed and the mass it carries from the electrical variables provided by the electronic variable speed drive.
Referring again to
In some example embodiments, the control device 108a may store data in the memory 508a, such as correlation data 510a. The correlation data 510a may include correlation information, for example, to correlate or infer between the input variables and the resultant output properties. The correlation data 510a may include, for example, the program map 302 (
In some example embodiments, the correlation data 510a stores the correlation information for some or all of the other devices 102, such as the second control pump 102b (
Referring still to
In some example embodiments, some or all of the correlation application 514a and/or the co-ordination module 515a may alternatively be part of the external controller 116.
In some example embodiments, in an example mode of operation, the control device 108a is configured to receive the input variables from its input subsystem 522a, and send such information as detection data (e.g. uncorrelated measured data) over the communications subsystem 516a to the other controller 116 or to the second control device 108b, for off-device processing which then correlates the detection data to the corresponding output properties. The off-device processing may also determine the aggregate output properties of all of the control devices 108a, 108b, for example to output properties 114 of a common load. The control device 108a may then receive instructions or commands through the communications subsystem 516a on how to control the output subsystems 520a, for example to control the local device properties or operable elements.
In some example embodiments, in another example mode of operation, the control device 108a is configured to receive input variables of the second control device 108b, either from the second control device 108b or the other controller 116, as detection data (e.g. uncorrelated measured data) through the communications system 516a. The control device 108a may also self-detect its own input variables from the input subsystem 522a. The correlation application 514a may then be used to correlate the detection data of all of the control devices 108a, 108b to their corresponding output properties. In some example embodiments, the co-ordination module 515a may determine the aggregate output properties for all of the control devices 108a, 108b, for example to the output properties 114 of a common load. The control device 108a may then send instructions or commands through the communications subsystem 516a to the other controller 116 or the second control device 108b, on how the second control device 108b is to control its output subsystems, for example to control its particular local device properties. The control device 108a may also control its own output subsystems 520a, for example to control its own device properties to the first control pump 102a (
In some other example embodiments, the control device 108a first maps the detection data to the output properties and sends the data as correlated data (e.g. inferred data). Similarly, the control device 108a can be configured to receive data as correlated data (e.g. inferred data), which has been mapped to the output properties by the second control device 108b, rather than merely receiving the detection data. The correlated data may then be co-ordinated to control each of the control devices 108a, 108b.
Referring again to
Reference is now made to
In another example embodiment, the method 800 may include a decision to turn on or turn off one or more of the control pumps 102, based on predetermined criteria. For example, the decision may be made using Equation 2 and Equation 3, as detailed above.
While the method 800 illustrated in
For example, referring to
Reference is now made to
A co-ordination module 602 is shown, which may either be part of at least one of the control devices 108a, 108b, or a separate external device such as the controller 116 (
In operation, the co-ordination module 602 co-ordinates the control devices 108a, 108b to produce a co-ordinated output(s). In the example embodiment shown, the control devices 108a, 108b work in parallel to satisfy a certain demand or shared load 114, and which infer the value of one or more of each device output(s) properties by indirectly inferring them from other measured input variables and/or device properties. This co-ordination is achieved by using the inference application 514a, 514b which receives the measured inputs, to calculate or infer the corresponding individual output properties at each device 102 (e.g. head and flow at each device). From those individual output properties, the individual contribution from each device 102 to the load (individually to output properties 114) can be calculated based on the system/building setup. From those individual contributions, the co-ordination module 602 estimates one or more properties of the aggregate or combined output properties 114 at the system load of all the control devices 108a, 108b. The co-ordination module 602 compares with a setpoint of the combined output properties (typically a pressure variable), and then determines how the operable elements of each control device 108a, 108b should be controlled and at what intensity.
It would be appreciated that the aggregate or combined output properties 114 may be calculated as a linear combination or a non-linear combination of the individual output properties, depending on the particular property being calculated, and to account for losses in the system, as appropriate.
In some example embodiments, when the co-ordination module 602 is part of the first control device 108a, this may be considered a master-slave configuration, wherein the first control device 108a is the master device and the second control device 108b is the slave device. In another example embodiment, the co-ordination module 602 is embedded in more of the control devices 108a, 108b than actually required, for fail safe redundancy.
Referring still to
Referring still to
However, if one of the control pumps (e.g. first control pump 102a) is determined to be underperforming or off of its control curve 208, the co-ordination module 602 may first attempt to control the first control pump 102a to operate onto its control curve 208. However, if this is not possible (e.g. damaged, underperforming, would result in outside of operation range 202, otherwise too far off control curve 208, etc.), the remaining control pumps (e.g. 102b) may be controlled to increase their device properties on their respective control curves 208 in order to achieve the pressure setpoint at the required flow at the output properties 114, to compensate for at least some of the deficiencies of the first control pump 102a. Similarly, one of the control pumps 102 may be intentionally disabled (e.g. maintenance, inspection, save operating costs, night-time conservation, etc.), with the remaining control pumps 102 being controlled accordingly.
In other example embodiments, the distribution between the output subsystems 520a, 520b may be dynamically adjusted over time so as to track and suitably distribute wear as between the control pumps 102.
Reference is now made to
As shown, the first co-ordination module 515a receives the inferred and/or measured values and calculates the individual output properties of each device 102 (e.g. head and flow). From those individual output properties, the individual contribution from each device 102 to the load (individually at output properties 114) can be calculated based on the system/building setup. The first co-ordination module 515a can then calculate or infer the aggregate output properties 114 at the load.
The first co-ordination module 515a then compares the inferred aggregate output properties 114 with a setpoint of the output properties (typically a pressure variable setpoint), and then determines the individual allocation contribution required by the first output subsystem 520a (e.g. calculating 50% of the total required contribution in this example). The first output subsystem 520a is then controlled and at a controlled intensity (e.g. increase, decrease, or maintain the speed of the motor, or other device properties), with the resultant co-ordinated output properties being again inferred by further measurements at the input subsystem 522a, 522b.
As shown in
As shown in
Reference is now made to
Reference is now made to
For the pump unit 1800, the connection between the pump motor and respective pump impeller can be split into two separate shafts, and further includes a pump seal (not shown). In an example embodiment, this connection is axially split, and a spacer type rigid coupling permits seal maintenance without disturbing the pump impeller and/or pump motor. For example, there can be a front removable cover 1836 and a rear removable cover 1837. When the cover 1836, 1837 is removed, the seal (not shown) for each pump motor within the pedestal casing can be replaced without removing the respective pump motor, for example.
In example embodiments, example screenshots of the touchscreen 1720, 1820 are illustrated in
Although example embodiments have been primarily described with respect to one pump unit, in some example embodiments a plurality of such pump units can be used in a system, for example arranged in parallel. In some example embodiments the pump units can be arranged in series, for example for a pipeline, booster, or other such application. The resultant output properties may still be co-ordinated in such example embodiments. For example, the output setpoint and output properties for the load may be the located at the end of the series. The control of the output subsystems, device properties, and operable elements may still be performed in a co-ordinated manner in such example embodiments. In some example embodiments, the pump units can be arranged in a combination of series and parallel.
Variations may be made in example embodiments. Some example embodiments may be applied to any variable speed device, and not limited to variable speed control pumps. For example, some additional embodiments may use different parameters or variables, and may use more than two parameters (e.g. three parameters on a three dimensional graph). For example, the speed (rpm) is also illustrated on the described control curves. Further, temperature (Celsius/Fahrenheit) versus temperature load (Joules or BTU/hr) may be parameters or variables which are considered for control curves, for example controlled by a variable speed circulating fan. Some example embodiments may be applied to any devices which are dependent on two or more correlated parameters. Some example embodiments can include selection ranges dependent on parameters or variables such as liquid, temperature, viscosity, suction pressure, site elevation and number of pump operating.
In example embodiments, as appropriate, each illustrated block or module may represent software, hardware, or a combination of hardware and software. Further, some of the blocks or modules may be combined in other example embodiments, and more or less blocks or modules may be present in other example embodiments. Furthermore, some of the blocks or modules may be separated into a number of sub-blocks or sub-modules in other embodiments.
While some of the present embodiments are described in terms of methods, a person of ordinary skill in the art will understand that present embodiments are also directed to various apparatus such as a server apparatus including components for performing at least some of the aspects and features of the described methods, be it by way of hardware components, software or any combination of the two, or in any other manner. Moreover, an article of manufacture for use with the apparatus, such as a pre-recorded storage device or other similar non-transitory computer readable medium including program instructions recorded thereon, or a computer data signal carrying computer readable program instructions may direct an apparatus to facilitate the practice of the described methods. It is understood that such apparatus, articles of manufacture, and computer data signals also come within the scope of the present example embodiments.
While some of the above examples have been described as occurring in a particular order, it will be appreciated to persons skilled in the art that some of the messages or steps or processes may be performed in a different order provided that the result of the changed order of any given step will not prevent or impair the occurrence of subsequent steps. Furthermore, some of the messages or steps described above may be removed or combined in other embodiments, and some of the messages or steps described above may be separated into a number of sub-messages or sub-steps in other embodiments. Even further, some or all of the steps of the conversations may be repeated, as necessary. Elements described as methods or steps similarly apply to systems or subcomponents, and vice-versa.
The term “computer readable medium” as used herein includes any medium which can store instructions, program steps, or the like, for use by or execution by a computer or other computing device including, but not limited to: magnetic media, such as a diskette, a disk drive, a magnetic drum, a magneto-optical disk, a magnetic tape, a magnetic core memory, or the like; electronic storage, such as a random access memory (RAM) of any type including static RAM, dynamic RAM, synchronous dynamic RAM (SDRAM), a read-only memory (ROM), a programmable-read-only memory of any type including PROM, EPROM, EEPROM, FLASH, EAROM, a so-called “solid state disk”, other electronic storage of any type including a charge-coupled device (CCD), or magnetic bubble memory, a portable electronic data-carrying card of any type including COMPACT FLASH, SECURE DIGITAL (SD-CARD), MEMORY STICK, and the like; and optical media such as a Compact Disc (CD), Digital Versatile Disc (DVD) or BLU-RAY Disc.
Variations may be made to some example embodiments, which may include combinations and sub-combinations of any of the above. The various embodiments presented above are merely examples and are in no way meant to limit the scope of this disclosure. Variations of the innovations described herein will be apparent to persons of ordinary skill in the art having the benefit of the present disclosure, such variations being within the intended scope of the present disclosure. In particular, features from one or more of the above-described embodiments may be selected to create alternative embodiments comprised of a sub-combination of features which may not be explicitly described above. In addition, features from one or more of the above-described embodiments may be selected and combined to create alternative embodiments comprised of a combination of features which may not be explicitly described above. Features suitable for such combinations and sub-combinations would be readily apparent to persons skilled in the art upon review of the present disclosure as a whole. The subject matter described herein intends to cover and embrace all suitable changes in technology.
This application is a continuation of U.S. patent application Ser. No. 16/461,274 filed May 15, 2019 entitled DUAL BODY VARIABLE DUTY PERFORMANCE OPTIMIZING PUMP UNIT, which is a U.S. nationalization under 35 U.S.C. § 371 of International Application No. PCT/CA2017/050648 filed May 29, 2017 entitled DUAL BODY VARIABLE DUTY PERFORMANCE OPTIMIZING PUMP UNIT, which claims the benefit of priority to U.S. Provisional Patent Application No. 62/451,219 filed Jan. 27, 2017, all the contents of which are herein incorporated by reference.
Number | Date | Country | |
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62451219 | Jan 2017 | US |
Number | Date | Country | |
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Parent | 16461274 | May 2019 | US |
Child | 18206537 | US |