Pump with high torque driver

Abstract

This invention discloses a pump with a high-torque drive and a fluid moving device (12) including an electric motor (24) having a rotor (42) and a stator (44) and a fluid displacement member (34). The rotor (42) rotates relative to the stator (44) on a common axis (CA) to produce a rotational output. The rotational output is provided to the fluid displacement member (34) to power the fluid displacement member (34) to perform one of linear movement along the common axis and rotation about the common axis. The stator (44) includes a plurality of coils (52) configured to power the rotation of the rotor (42). The plurality of coils (52) are arranged along the common axis (CA).

Description

[0001] This application is a divisional application of the patent application filed on March 31, 2021, with national application number 202180026336.3 and invention title "Pump with High Torque Driver".

[0002] Cross-references to related applications

[0003] This application claims the benefit of U.S. Provisional Application No. 63 / 003,021, filed on March 31, 2020, entitled "Pump with High Torque Drive," the entire contents of which are incorporated herein by reference. Technical Field

[0004] This disclosure relates to pump systems. More specifically, this disclosure relates to drives for fluid moving equipment (e.g., pump equipment) used in a variety of applications. Background Technology

[0005] Typically, the fluid being pumped is pressurized by a positive displacement pump. In coating applications, the pump pressurizes the paint and delivers it under pressure through a flexible hose. A spray gun is used to dispense the paint, and it is connected to the end of the hose opposite to the pump. Positive displacement pumps are typically mounted on a drive housing and driven by an electric motor. A pump rod is attached to a reciprocating drive that drives the pump rod to reciprocate, thereby drawing fluid from the container into the pump and then driving the fluid downstream from the pump. In some cases, an electric motor can power the pump. The electric motor is connected to the pump via a gear reduction system that increases the torque generated by the electric motor. Summary of the Invention

[0006] According to one aspect of this disclosure, a pumping device for pumping fluid includes: an electric motor configured to generate a rotary output; a driver configured to convert the rotary output from the electric motor into a linear reciprocating output; and a device configured to receive the linear reciprocating output from the driver to linearly reciprocate along a common axis to pump fluid. The electric motor includes: a rotor configured to rotate about the common axis, the rotor including a plurality of magnets, each magnet being elongated and extending parallel to the common axis, the plurality of magnets being arranged annularly around the common axis; and a stator configured to be energized to generate a magnetic flux that rotates the rotor. The stator includes a plurality of coils arranged along the common axis, each of the plurality of coils being coaxial with the common axis; and a plurality of circular spike arrays arranged along the common axis, each of the plurality of circular spike arrays including a plurality of spikes arranged in a circle coaxial with the common axis, all spikes of the plurality of circular spike arrays being configured to be simultaneously polarized by the coils of the plurality of coils to generate a magnetic flux, causing the rotor to rotate relative to the stator.

[0007] According to an additional or alternative aspect of this disclosure, a pumping device includes: an electric motor including a stator and a rotor coaxially rotating about a common axis, the stator including a plurality of coils arranged along the common axis; a fluid displacement member configured to linearly reciprocate along the common axis to pump fluid; and a drive mechanism axially located between the electric motor and a piston, which converts a rotational output from the electric motor into a linear reciprocating output driving the fluid displacement member. The drive mechanism is configured such that the fluid displacement member travels one inch for every first number of full revolutions of the electric motor, wherein the first number is in the range of 0.9-3.0 revolutions, inclusive.

[0008] According to another additional or alternative aspect of this disclosure, a pumping device includes: an electric motor including a stator and a rotor rotating about a common axis, the stator including a plurality of coils arranged along the common axis; a fluid displacement member configured to linearly reciprocate along the common axis CA to pump fluid; and a drive mechanism located between the electric motor and a piston, converting the rotational output of the electric motor into a linear reciprocating output driving the piston. The drive mechanism is configured such that the fluid displacement member completes one pump stroke for every X number of full revolutions of the electric motor, wherein X is in the range of 1-3, inclusive.

[0009] According to another additional or alternative aspect of this disclosure, a pumping device includes: an electric motor including a stator and a rotor rotating about a common axis, the stator including a plurality of coils arranged along the common axis, each coil surrounding and extending around and coaxial with the common axis; a cylindrical piston coaxial with the common axis, the piston being configured to reciprocate linearly along the common axis to pump fluid; and a drive mechanism located between the electric motor and the piston, converting the rotational output of the electric motor into a linear reciprocating output driving the piston.

[0010] According to another additional or alternative aspect of this disclosure, an apparatus for moving a liquid includes an electric motor configured to generate a rotary output and a fluid displacement member configured to move the liquid by rotating a rotor about a common axis. The electric motor includes: a rotor configured to rotate about the common axis, the rotor including a plurality of magnets, each magnet being elongated and extending parallel to the common axis, the plurality of magnets being arranged annularly about the common axis; and a stator configured to be energized to generate a magnetic flux that rotates the rotor. The stator includes: a plurality of coils arranged along the common axis, each of the plurality of coils being coaxial with the common axis; and a plurality of circular spike arrays arranged along the common axis, each of the plurality of circular spike arrays including a plurality of spikes arranged in a circle coaxial with the common axis, the plurality of circular spikes being configured to be simultaneously polarized by the coils of the plurality of coils to generate a magnetic flux, thereby causing the rotor to rotate relative to the stator.

[0011] According to another additional or alternative aspect of this disclosure, a device for moving a liquid includes an electric motor configured to generate a rotary output and a fluid displacement member configured to move via the output of the electric motor. The electric motor includes a rotor configured to rotate about a common axis, the rotor including a plurality of magnets, each magnet being elongated and extending parallel to the common axis, the plurality of magnets being arranged in a ring around the common axis; a stator is configured to be energized to generate a magnetic flux that rotates the rotor. The stator includes a plurality of coils arranged along the common axis, each of the plurality of coils being coaxial with the common axis. A plurality of circular spike arrays are arranged along the common axis, each of the plurality of circular spike arrays including a plurality of spikes arranged in a circle coaxial with the common axis, the plurality of circular spikes being configured to be simultaneously polarized by the coils of the plurality of coils to generate a magnetic flux, causing the rotor to rotate relative to the stator. At least one spike of the stator is closer to the fluid displacement member than any one of the coils. Attached Figure Description

[0012] Figure 1A This is a frontal schematic block diagram of the pump equipment.

[0013] Figure 1B yes Figure 1A A schematic block diagram of the pump equipment from the side.

[0014] Figure 2 This is a schematic block diagram of the pump equipment.

[0015] Figure 3A Is Figure 1A and Figure 1B A three-dimensional view of the pump components used in the pump system.

[0016] Figure 3B It is along Figure 3A The three-dimensional sectional view taken by line BB in the figure.

[0017] Figure 3C It is along Figure 3A The first frontal section view is taken from line BB in the middle.

[0018] Figure 4A It is a three-dimensional view showing a portion of the electric motor in isolation.

[0019] Figure 4B yes Figure 4A The image shows a three-dimensional view of the stator of the electric motor.

[0020] Figure 5A yes Figure 4B A three-dimensional view of the phase assembly of the stator shown.

[0021] Figure 5B yes Figure 5A The diagram shows a three-dimensional view of the phase assembly, in which the flux loop has been removed for clarity.

[0022] Figure 6A It is an enlarged cross-sectional view showing the current flowing through the phase component.

[0023] Figure 6B It is shown that... Figure 6A An enlarged cross-sectional view of the currents opposite to those shown.

[0024] Figure 6C This is an enlarged end-face view showing the magnetic polarity of a component in the rotor section of an electric motor.

[0025] Figure 7 This is a schematic block diagram of the pump equipment.

[0026] Figure 8 This is a schematic block diagram of the pump equipment.

[0027] Figure 9 This is a schematic block diagram of the pump equipment.

[0028] Figure 10 This is a schematic block diagram of the pump equipment.

[0029] Figure 11 This is a schematic block diagram of the pump equipment.

[0030] Figure 12A This is a schematic block diagram of existing pump equipment.

[0031] Figure 12B This is an end view of a conventional electric motor. Detailed Implementation

[0032] This disclosure relates to a pumping device having an electric motor rotating about a common axis and a pumping component reciprocating along the common axis. The electric motor and the pumping component are coaxial on the common axis. The electric motor includes a rotor rotating about the common axis and a stator energized to generate magnetic flux that rotates the rotor. The stator includes one or more coils, each coaxial with the common axis.

[0033] Figure 1A This is a frontal schematic block diagram of the pump system 10. Figure 1B This is a side view schematic block diagram of pump system 10. It will be discussed together. Figure 1A and Figure 1B In this embodiment, the pump system 10 is configured as a spray system, for example, for spraying paint or other liquids. However, the pump system 10 can be configured for other pumping and fluid handling applications, such as position transfer, loading and unloading, spraying, metering, coating, etc. Pump device 12, support 14, spray gun 16, supply line 18, and reservoir 20 are shown. Pump device 12 includes a pump frame 22, motor 24, driver 26, displacement pump 28, and controller 29. Support 14 includes a support frame 30 and wheels 32. Fluid displacement member 34 and pump body 36 of displacement pump 28 are shown. Spray gun 16 includes a handle 38 and trigger 40.

[0034] The pump system 10 in this embodiment is a system for applying jets of various fluids to a substrate. Examples of fluids include paints, water, oils, stains, finishing materials, aggregates, covering materials, and solvents, among others. The pump device 12 can generate high fluid pumping pressures, such as about 3.4–69 MPa (about 500–10,000 psi) or even lower and / or higher. In some examples, the pumping pressure is in the range of about 20.7–34.5 MPa (about 2,000–4,000 psi). High fluid pumping pressures are useful for atomizing fluids into jets for application to a surface. While the jetting system version of pump system 10 describes pump device 12, it should be understood that pump device 12 can be used for pumping in any desired system. For example, pump device 12 can be used as a delivery pump to deliver fluids; it can be used in multi-component jetting systems, such as supplying component fluids to a proportioning pump; for proportioning pumps; for loading and unloading; for metering; for coating, etc.

[0035] Pump device 12 is configured to draw jet fluid from reservoir 20 and pump the fluid to downstream spray gun 16 for application onto a substrate. Support 14 is connected to and supports pump device 12 relative to reservoir 20. Support frame 30 is connected to pump frame 22. Wheels 32 are connected to support frame 30 to facilitate movement between and within work sites. Although pump device 12 is described as being supported by support 14, it should be understood that pump device 12 can be mounted to draw fluid in any desired manner. For example, pump device 12 can be mounted on the cap of reservoir 20 such that reservoir 20 supports pump device 12. Pump device 12 can be mounted directly to reservoir 20. For example, the reservoir can be a drum, such as a 55-gallon drum, among other options, and pump device 12 can be mounted directly to the drum. In such an example, pump device 12 can be referred to as a drum pump.

[0036] Pump frame 22 supports other components of pump unit 12. Electric motor 24 and positive displacement pump 28 are connected to pump frame 22. Electric motor 24 is an electric motor having a stator and a rotor. The rotor is configured to rotate about a rotation axis in response to current flowing through the stator. The rotation axis is coaxial with the common axis CA shown in the figure. Electric motor 24 produces a rotational output coaxial with the common axis CA.

[0037] Unless otherwise stated, the terms "radial" or "radially / in the radial direction" as used herein mean orthogonal to the common axis CA. Unless otherwise stated, the terms "axial" or "axially / in the axial direction" as used herein mean parallel to the common axis CA. Unless otherwise stated, the terms "circumferential" or "circumferentially / in the circumferential direction" as used herein mean about the common axis CA.

[0038] Controller 29 is operatively connected to motor 24, electrically and / or communicatively, to control the operation of motor 24. Controller 29 thereby controls the pumping of positive displacement pump 28. Controller 29 may have any desired configuration for controlling the pumping of positive displacement pump 28 and may include control circuitry and memory. Controller 29 is configured to store executable code, implement functions, and / or process instructions. Controller 29 is configured to perform any functions discussed herein, including receiving outputs from any sensors mentioned herein, detecting any conditions or events mentioned herein, and controlling the operation of any components mentioned herein. Controller 29 may have any suitable configuration for controlling the operation of pumping device 12, collecting data, processing data, etc. Controller 29 may include hardware, firmware, and / or stored software. Controller 29 may be of any type suitable for operation according to the techniques described herein. Although controller 29 is shown as a single unit, it is understood that controller 29 may be entirely or partially disposed on one or more circuit boards. In some examples, controller 29 may be implemented as multiple discrete circuit sub-components.

[0039] A driver 26 is connected to and driven by a motor 24. The driver 26 receives the rotational output from the motor 24 and converts it into a linear input along a common axis CA. The driver 26 is (directly or indirectly) connected to a fluid displacement member 34 to drive the fluid displacement member 34 to reciprocate along the common axis CA. In some examples, the motor 24, driver 26, and fluid displacement member 34 are coaxially arranged on the common axis CA. Thus, the rotational axis of the motor 24 and the reciprocating axis of the fluid displacement member 34 are coaxial. The fluid displacement member 34 reciprocates within a pump body 36 to pump jet fluid from the reservoir 20 through the supply line 18 to the spray gun 16. The fluid displacement member 34 may be cylindrical, elongated along the common axis CA, and coaxial with the common axis CA. In some examples, the fluid displacement member 34 may be a piston, which may be elongated along the common axis CA and coaxial with the common axis CA. In some examples, the fluid displacement member 34 may be a diaphragm in which its center reciprocates linearly while its circular outer periphery remains in place. The diaphragm may be coaxial with a common axis CA, such that the center of the diaphragm is on the common axis CA and reciprocates linearly along the common axis CA.

[0040] During operation, the user can manipulate the pump device 12 to a desired position relative to a target base or other pumping applications by moving the support 14. For example, the user can manipulate the pump device 12 by tilting the support frame 30 on the wheels 32 and rolling the pump device 12 to the desired position. The pump device 12 can be handheld, meaning that people can move the pump device 12 to and around the work site by hand. In some embodiments, the pump device 12 is light enough to be picked up (e.g., less than about 31.8 kg (less than about 70 lbs)) and carried. In some cases, the pump device 12 is wheeled to allow transport, as described above. In some cases, the weight of the pump device 12 may be less than about 45.4 kg (about 100 lbs), or in some cases less than about 68.0 kg (about 150 lbs), or in some cases less than about 90.7 kg (about 200 lbs).

[0041] A positive displacement pump 28 may extend into the reservoir 20. An electric motor 24 provides a rotary input to a driver 26, and the driver 26 provides a linear input to a fluid displacement member 34 to induce reciprocating motion of the fluid displacement member 34. The rotor of the electric motor 24 rotates on a common axis CA to produce a rotary output. The rotary output from the electric motor 24 is provided as a rotary input to the driver 26, which converts the rotary input from the electric motor 24 into a linear output, which is provided as a linear input to the fluid displacement member 34. The linear input to the fluid displacement member 34 from the driver 26 induces linear displacement of the fluid displacement member 34 on the common axis CA. The fluid displacement member 34 draws fluid from the reservoir 20, pressurizes the fluid, and drives the fluid downstream through the supply line 18 to the spray gun 16. The user can operate the spray gun 16, for example, by gripping the handle 38 with one hand. The user induces a spray by actuating the trigger 40. In some examples, the pressure generated by the pump device 12 atomizes the fluid leaving the spray gun 16 to produce a fluid spray. In some examples, spray gun 16 is an airless atomizer, which means that the pressure acting solely on the fluid and generated by pump device 12 propels and atomizes the fluid, while the airflow is not used to propel and atomize the fluid into a spray.

[0042] Figure 2 This is a schematic block diagram of pump assembly 12. Pump assembly 12 includes a motor 24, a driver 26, and a positive displacement pump 28. It shows the rotor 42 and stator 44 of the motor 24. The rotor 42 includes a permanent magnet array 46 and a rotor body 48. The stator 44 includes phase assemblies 50, each phase assembly including a coil 52. The driver 26 includes a drive nut 54 and a screw 56. The positive displacement pump 28 includes a pump body 36, a fluid displacement member 34, and check valves 58a and 58b.

[0043] Motor 24 is an electric motor. Rotor 42 is configured to rotate relative to stator 44 on a rotation axis AR. Stator 44 is coaxially disposed with rotor 42 on the rotation axis AR. The rotation axis AR is coaxial with a common axis CA. Rotor 42 includes a permanent magnet array 46 oriented toward stator 44. In the illustrated example, rotor 42 is disposed around stator 44 and permanent magnet array 46 is disposed radially inside rotor body 48. Air gap 60 is formed between stator 44 and rotor 42 such that stator 44 and rotor 42 do not directly contact each other. More specifically, air gap is formed radially between stator 44 and permanent magnet array 46. Therefore, electric motor 24 can be considered to include an outer rotor. However, it should be understood that in various other examples, rotor 42 is disposed within stator 44 to rotate within stator 44, such that electric motor 24 can be considered to include an inner rotor. In such examples, permanent magnet array 46 may be disposed on the outer radial surface of rotor body 48.

[0044] The stator 44 includes phase assemblies 50 arranged along and around the axis of rotation AR. Each phase assembly 50 includes a coil 52 extending circumferentially about a common axis CA. Each phase assembly 50 includes a metal component formed on each axial side of the coil 52. The metal component may be formed wholly or partially of a stack of layers. The stack may be formed of a material that is readily polarized by the field generated by the coil 52. This material is typically ferromagnetic. The ferromagnetic material may be a metal, such as iron or an iron alloy, such as steel. More specifically, the stack may be made of silicon steel and other options. The ferromagnetic material may be a ceramic doped or embedded with ferromagnetic elements.

[0045] Coil 52 is formed as a wire hoop extending circumferentially around a common axis CA. Therefore, coil 52 is coaxial with the common axis CA. Each coil 52 is discrete relative to the other coils 52. Each coil 52 is a wire (typically copper) winding around the common axis CA. Therefore, each coil 52 can be a continuous winding of 20, 30, 40, 50, 100, or fewer or more turns around the common axis CA. In some embodiments, a ribbon is wound instead of a wire. Each coil 52 has two terminal lines representing the circuit ends of each coil 52 for running AC signals through the coil 52, which can be connected to controller 29 ( Figure 1A and Figure 1B Electrical connection.

[0046] The coils 52 do not overlap or cross each other radially. No part of any coil 52 is positioned along the common axis CA at the same axial location as any other coil 52. Therefore, no coil 52 overlaps radially with any other coil 52. An axial gap exists between each coil 52 of the motor 24. Therefore, the coils 52 are located at separate and distinct axial locations along the common axis CA. Each coil 52 is made of a circular coil. The common axis CA extends through each loop of each coil 52. Loops in the coils 52 through which the common axis CA does not extend are excluded. The wires of the loops do not extend axially but circumferentially around the common axis CA.

[0047] A positive displacement pump 28 is disposed at the axial end of the pumping device 12 opposite to the motor 24. A fluid displacement member 34 (e.g., a piston or diaphragm, and other options) is configured to reciprocate along a reciprocating axis RA. The reciprocating axis RA is coaxial with a common axis CA. The reciprocating axis RA is also coaxial with a rotational axis AR. The fluid displacement member 34 reciprocates within a pump body 36 to pump fluid. Both the pump body 36 and the fluid displacement member 34 may be coaxial with the common axis CA. In some examples, the pump body 36 is a cylinder / cylinder. For example, the pump body 36 may be a cylinder, and the fluid displacement member 34 may be a piston that is axially elongated along the reciprocating axis Ra, both coaxially disposed with respect to the rotor 42 and the stator 44 on the common axis CA.

[0048] A actuator 26 extends and connects between the motor 24 and the fluid displacement member 34. In the example shown, the actuator 26 includes a screw 56 and a drive nut 54. The elongated screw 56 is coaxial with a common axis CA, and therefore with the reciprocating axis RA and the rotary axis AR. Depending on the mechanical design of the pump assembly 12, the elongated screw 56 may rotate on the common axis CA without linear reciprocating motion, or the elongated screw 56 may reciprocate linearly along the common axis CA without rotation. The drive nut 54 is coaxial with the common axis CA and therefore with the reciprocating axis RA and the rotary axis AR. The drive nut 54 may be one of two cases: in the embodiment where the screw 56 reciprocates linearly, the drive nut 54 may rotate on the common axis CA; or in the embodiment where the screw 56 rotates on the common axis CA but does not reciprocate linearly, the drive nut 54 may reciprocate along the common axis CA.

[0049] The rotating component of the driver 26 (e.g., the first of the drive nut 54 and screw 56) is connected to the rotor 42 to receive the rotational output from the motor 24. The reciprocating component of the driver 26 (e.g., the other of the drive nut 54 and screw 56) is connected to the fluid displacement member 34 to provide a linear input to the fluid displacement member 34 to drive the axial reciprocating motion of the fluid displacement member 34.

[0050] Although at least a portion of the drive 26 is axially disposed between the motor 24 and the positive displacement pump 28, it should be understood that one or more components of the drive 26 may radially overlap with one or more components of the motor 24. These components can be considered radially overlapping when they are arranged in a common axial position along a common axis CA. A radial line extending from the common axis CA will extend through each radially overlapping component. For example, the drive nut 54 may be radially inside the rotor 42 (particularly in embodiments where the rotor 42 is located within and rotates within the stator 44) to linearly drive the screw 56. In some examples, the screw 56 is at least partially disposed within the hollow core of the motor 24 (the hollow core extends through the rotor 42 and is coaxial with the rotor 42 and the common axis CA). In some examples, the amount of overlap between the linear displacement elements of the motor 24 and the drive 26 may vary during operation. For example, the axial end of the screw 56 may be disposed within the motor 24 and axially movable relative to the motor 24 along the common axis CA, such that the amount of overlap increases and decreases. Therefore, at least a portion of the reciprocating motion region of the reciprocating motion component (i.e., the region along the common axis between the far ends of the linear travel range of the reciprocating motion component) can be both coaxial and located in the same position as at least a portion of the rotor region of the rotation axis (i.e., the region where the rotor 42 is located along the rotation axis).

[0051] During operation, power is supplied to coil 52 and phase assembly 50 generates an electromagnetic field that interacts with permanent magnet array 46 to drive rotor 42 to rotate. The illustrated embodiment of motor 24 includes three phases corresponding to three phase assemblies 50 and coils 52 therein, wherein three sinusoidal AC signals (electrically offset by 120 degrees) are transmitted through coils 52. If there are two phase assemblies 50 and two coils 52, the two sinusoidal AC signals will be 180 degrees apart, or for a group of four phase assemblies 50, they will be 90 degrees apart, and so on.

[0052] Rotor 42 rotates about a common axis CA and generates a rotational output. This rotational output is provided to driver 26, which converts the rotational motion into linear motion along the common axis CA. The linear output generated by driver 26 is provided to fluid displacement member 34 to cause it to linearly displace along the common axis CA. In some examples, motor 24 is a reversible motor, such that rotor 42 is driven in a first rotational direction (e.g., one of clockwise and counterclockwise directions) to move fluid displacement member 34 in a first axial direction AD1 and rotor 42 is driven in a second rotational direction (e.g., the other of clockwise and counterclockwise directions) to move fluid displacement member 34 in a second axial direction AD2.

[0053] In the example shown, the positive displacement pump 28 is a dual positive displacement pump configured to output fluid both when the fluid displacement member 34 is driven along a first axial direction AD1 and when the fluid displacement member 34 is driven along a second axial direction AD2. In the example shown, the fluid displacement member 34 is a piston and a check valve 58b is mounted to the piston to travel axially with the piston. As the fluid displacement member 34 moves along the second axial direction AD2, the check valve 58a opens and the check valve 58b closes. Fluid is drawn into the upstream chamber of the pump body 36 through the check valve 58a, which is axially positioned between the check valves 58a and 58b. Fluid in the downstream chamber of the check valve 58b, located on the axial side opposite to the upstream chamber, is driven downstream from the positive displacement pump 28. As the fluid displacement member 34 moves along the first axial direction AD1, the check valve 58a closes and the check valve 58b opens. The closed check valve 58a prevents backflow from the upstream chamber. Fluid is driven from the upstream chamber through the check valve 58b and into the downstream chamber. Fluid is also driven downstream from the downstream chamber by the positive displacement pump 28. Therefore, the positive displacement pump 28 can output fluid during each stroke of the fluid shifting member 34.

[0054] Traditional AC induction motors use multiple discrete coils that extend axially and form a coil array that extends circumferentially around the rotor's axis of rotation (see [link]). Figures 12A-12B Each coil represents a potential pole acting on a magnet. In a conventional AC induction motor, discrete coils arranged circumferentially around the axis of rotation are out of phase. The resulting potential torque is proportional to the number of poles. The number of poles in such a motor is limited by the ability to circumferentially mount discrete coils around the axis of rotation within the motor.

[0055] The coil 52, extending circumferentially around the common axis CA, allows for more poles than a conventional AC induction motor. This increased number of poles allows for a more even distribution of force across the circumference of the rotor 42, minimizing or eliminating eccentric forces or unproductive portions of the force. Coordinating the rotation axis AR of the rotor 42 with the reciprocating axis RA of the shifting member 34 on the common axis CA further minimizes eccentric forces. The high pole number eliminates or reduces the need for reduction gearing, further reducing eccentric forces and lightening weight and friction, allowing for a more compact arrangement of the pump unit 12. Even at low pumping speeds with minimal or no gear reduction, the design of this motor 24 still favors high torque (which generates high fluid pressure), further reducing cost, weight, friction, and packaging size. Coaxiality of the rotation axes of the rotor 42, the elongated screw 56, and the shifting member 34 relative to each other (e.g., along the common axis CA) allows for a compact and efficient pump design.

[0056] There is no mechanical amplification device (mechanically reducing speed to increase torque) between the rotary output of motor 24 and the linear reciprocating input to piston pump 28. While motor 24 can produce high torque at low speeds (unlike conventional AC induction motors), it can also produce high torque at high speeds. Therefore, a single pump unit 12 can achieve many performance points (e.g., pressure relative to pumped volume) within a performance range that would otherwise require several different models of conventional motors driving the pump with specific gear reduction ratios, each specific to a sub-section of the same performance range. Pump unit 12 thus provides a wide range of possible operating conditions that would require multiple conventional pumps (each with a different driver) to achieve the same range.

[0057] Figure 3A This is a three-dimensional view of pump equipment 12. Figure 3B It is along Figure 3A The three-dimensional sectional view of pump equipment 12 taken from line BB in the figure. Figure 3C It is along Figure 3A The front sectional view taken by line BB in the diagram. This will be discussed together. Figures 3A-3C The pump frame 22, motor 24, driver 26, positive displacement pump 28, rotor shaft 62, bearing assembly 64, sensor 66, pump shaft 68, and timing component 70 are shown. The pump frame 22 includes a body 72, connector 74, and frame end 76. The body 72 includes a first portion 78, a second portion 80, a third portion 82, a mounting flange 84, a column 86, and a side opening 88. The frame end 76 includes a radial protrusion 90.

[0058] Motor 24 includes rotor 42, stator 44, motor bearing 92, shaft 94, first motor end 96, second motor end 98, and power connector 100. Rotor 42 includes rotor body 48 and permanent magnet array 46. The internal details of stator 44 and rotor 42 will be discussed further herein. Shaft 94 includes outer end 102.

[0059] The driver 26 includes a drive nut 54, a screw 56, and a rolling element 104. Figure 3B The drive nut 54 includes a nut mounting protrusion 106, a nut shoulder 108, and an axial extension 110. The screw 56 includes a first screw end 112, a second screw end 114, a thread 116, and a hole 118. The rotor shaft 62 includes a first shaft end 120 and a second shaft end 122.

[0060] The positive displacement pump 28 includes a fluid displacement component 34, a pump body 36, and check valves 58a and 58b. The fluid displacement component 34 includes a connector 108. The sensor 66 includes a first transducer component 126 and a second transducer component 128.

[0061] Motor 24 is disposed at the first axial end of pump assembly 12, and positive displacement pump 38 is disposed at the second axial end of pump assembly 12. Pump frame 22 supports other components of pump assembly 12. Motor 24 is axially disposed between frame end 76 and body 72. Motor 24 is an electric motor 24. Stator 44 includes coils 52 (e.g., Figure 2 and 4A - Figure 9 As shown (also referred to as the stator winding), the rotor 42 includes a permanent magnet array 46. The stator 44 and rotor 42 are coaxially arranged on a common axis CA. The rotor 42 is configured to rotate about the common axis CA in response to a current flowing through the stator 44. The motor 24 is a reversible motor because the stator 44 can cause the rotor 42 to rotate alternately about the common axis CA in two directions of rotation (e.g., clockwise or counterclockwise) to cause the fluid displacement member 34 to travel linearly in either a forward or backward direction along the common axis CA (e.g., along axial directions AD1 and AD2). For example, the rotor 42 can rotate in one of the clockwise and counterclockwise directions to drive the fluid displacement member 34 for a downward stroke along the axial direction AD1 and away from the motor 24, and then the rotor 42 can rotate in the other of the clockwise and counterclockwise directions to pull the fluid displacement member 34 towards the motor 24 by an upward stroke along the second axial direction AD2.

[0062] In the example shown, rotor 42 is arranged around stator 44 such that motor 24 includes an outer rotor. In various other embodiments, rotor 42 is arranged within stator 44 such that motor 24 includes an inner rotor, which still conforms to the principles of this disclosure. Permanent magnet array 46 faces stator 44 and is spaced from stator 44 by air gap 60 (preferably within...). Figure 2 (See shown in the image). In the example shown, the permanent magnet array 46 is disposed on the inner circumferential surface of the rotor body 48 because the rotor 42 is the outer rotor. The permanent magnet array 46 is arranged circumferentially around a common axis CA. The permanent magnet array 46 forms a ring array coaxially disposed on the common axis CA with the rotor 42 and the stator 44. The rotor body 48 can be formed from a single component or from multiple components fixed together.

[0063] Stator 44 is fixed to shaft 94. Shaft 94 extends along and is coaxially arranged with a common axis CA. The outer end portion 102 of shaft 94 extends beyond the axial end of stator 44 in a second axial direction AD2. The outer end portion 102 of shaft 94 extends beyond the axial end of rotor 42 in the second axial direction AD2. The outer end portion 102 axially protrudes beyond the second motor end 98. The outer end portion 102 of shaft 94 is open, thereby providing power to motor 24 through the second motor end 98. In the example shown, power connector 100 may be an electrical plug configured to connect to a socket (e.g., a wall socket), connected to stator 44 via a cable extending through the opening in the outer end portion 102 and connected to the coil 52 of stator 44. Thus, motor 24 can receive power through the second motor end 98 and provide rotational output through the first motor end 96. Motor bearing 92 supports rotor 42 relative to stator 44. Motor bearing 92 facilitates rotation of rotor 42 relative to stator 44. Shaft 94 extends through motor bearing 92 located at the second motor end 98 of motor 24, such that motor bearing 92 is located at the second motor end 98 between rotor body 48 and shaft 94.

[0064] Pump frame 22 supports motor 24. Body 72 extends relative to motor 24 in the axial direction AD1. In the example shown, body 72 is axially spaced from first motor end 96. Body 72 is spaced from first motor end 96 in the first axial direction AD1. Body 72 is coaxially arranged with common axis CA. Thus, body 72 is coaxially arranged with motor 24 and fluid displacement member 34 on common axis CA. Body 72 includes a first portion 78 axially closest to motor 24, a second portion 80 connected to and extending from first portion 78 in the first axial direction AD1, and a third portion 82 connected to and extending from second portion 80 in the first axial direction AD1. Although body 72 is shown as being formed of three portions, it should be understood that body 72 can be formed of as many or as few portions as needed. In the example shown, the width of each portion of body 72 orthogonal to common axis CA decreases as body 72 extends away from motor 24 and toward positive displacement pump 28. In the example shown, the width of the first portion 78 is greater than the width of the second portion 80. The width of the second portion 80 is greater than the width of the third portion 82, and the width of the third portion 82 is greater than the width of the pump body 36. A column portion 86 and a side opening 88 are formed in the end of the third portion 82 opposite to the second portion 80. The side opening 88 is formed between the column portions 86. The side opening 88 provides access to the connection between the fluid displacement member 34 and the pump shaft 68 to facilitate the installation and removal of the positive displacement pump 28.

[0065] The main body 72, formed by multiple parts, facilitates efficient assembly and maintenance of the pump assembly 12. The main body 72 can be disassembled to provide access to various components of the pump assembly 12, including dynamic, moving parts. For example, the second part 80 can be removed from the first part 78 to facilitate lubrication of the drive 26. It should be understood that in some examples, the drive 26 can be accessed and maintained without disassembling the main body 72. A bumper 130b is disposed in the third frame 62, on the side of the pump shaft 68 opposite to the drive nut 54. The bumper 130b can be compressible and can engage with the pump shaft 68 in the event of overtravel.

[0066] The frame end 56 is located on the axial side of the motor 24 opposite to the main body 72. The frame end 76 is located near the second motor end 98. The frame end 76 is fixed to the outer end 102 of the shaft 94. Through the connection between the shaft 94 and the frame end 76, the motor 24 is statically connected to the pump frame 22. The pump frame 22 fixes the motor 24 in an axial position along the common axis CA, and the connection between the pump frame 22 and the shaft 94 prevents the stator 44 from moving relative to the common axis CA.

[0067] Connector 74 extends between body 72 and frame end 76, and secures body 72 and frame end 76 together to prevent relative movement between frame end 76 and body 72. In the example shown, connector 74 is secured to the radial protrusion 90 of frame end 76 and connected to mounting flange 84 of body 72. Connector 74 secures body 72 and frame end 76 together to prevent unwanted relative movement between these components and unwanted movement of these components relative to common axis CA. Although pump frame 22 is described as being formed of multiple components, it should be understood that pump frame 22 serves as a single component to support motor 24 and positive displacement pump 28 and to respond to loads experienced during pumping, as discussed in more detail below. Pump frame 22 can be formed of as many or as few individual components as needed.

[0068] The connector 74 is radially spaced from the rotor 42 and extends axially between the frame end 76 and the body 72. The rotor 42 rotates within the region defined by the connector 74, the body 72, and the frame end 76. Although the connector 74 is shown as being formed by a plurality of connecting members spaced circumferentially around the rotor 42, it should be understood that in some examples, the connector 74 may completely surround the rotor 42. For example, one or more connectors 74 may form a housing in which the rotor 42 rotates. In the example shown, the connecting member 74 includes a plurality of tie rods that extend between the frame end 76 and the body 72 and connect the frame end 76 and the body 72.

[0069] Rotor 42 and rotor shaft 62 serve as the rotating output components of motor 24, which powers drive 26. Rotor shaft 62 is fixed to rotor 42 to rotate with rotor 42. Rotor shaft 62 rotates on the axis of rotation of rotor 42 and thus on a common axis CA. Rotor shaft 62 extends into the interior of body 72 such that at least a portion of rotor shaft 62 radially overlaps with at least a portion of body 72. In some examples, rotor shaft 62 may be removably connected to rotor 42, for example, by fasteners. It should be understood that in other examples, rotor shaft 62 may be integrally formed with rotor body 48. Rotor shaft 62 extends axially from rotor 42 along common axis CA and in a first axial direction AD1. Rotor shaft 62 is elongated along an axis coaxial with common axis CA. Rotor shaft 62 is coaxially arranged with stator 44, rotor 42, drive 26, and fluid displacement member 34. In the example shown, rotor shaft 62 includes an open first axial end 102 and a closed second axial end 104. The closed end is located at the interface between rotor shaft 62 and rotor 42. A buffer 130a is located in rotor shaft 62 at the closed end of rotor shaft 62. The buffer 130a may be compressible and may engage with the second screw end 114 in case of overtravel to prevent damage to screw 56.

[0070] Bearing assembly 64 is radially disposed between rotor shaft 62 and pump frame 22. More specifically, bearing assembly 64 is radially disposed between rotor shaft 62 and body 72. Bearing assembly 64 is axially disposed between drive nut 54 and motor 24. Bearing assembly 64 supports motor 24 relative to pump frame 22 and facilitates rotation of rotor shaft 62 relative to pump frame 22. Thus, bearing assembly 64 forms a dynamic connection between motor 24 and pump frame 22. Bearing assembly 64 is configured to support rotational and axial loads generated during pumping. Bearing assembly 64 supports axial loads to isolate motor 24 from axial loads generated by positive displacement pump 28. Bearing assembly 64 may be referred to as a thrust bearing.

[0071] The bearing assembly 64 can have any configuration suitable for supporting axial loads generated during pumping. In some examples, the bearing assembly 64 may include a single bearing element configured to support axial loads in each of the first axial direction AD1 and the second axial direction AD2, such as a double-row angular contact bearing. In some examples, the bearing assembly 64 may be formed of multiple bearing elements to support axial loads in each of the first axial direction AD1 and the second axial direction AD2. For example, the bearing assembly 64 may be formed of a first tapered roller bearing configured to support axial loads in the first axial direction AD1 and a second tapered roller bearing configured to support axial loads in the second axial direction AD2.

[0072] The drive 26 is coaxial with the common axis CA and operatively connected to the rotor shaft 62. The drive 26 is located at the axial end of the rotor shaft 62 opposite to the rotor 42. The drive 26 receives the rotational output from the rotor 42 via the rotor shaft 62. The drive 26 is supported by the pump frame 22 via the bearing assembly 64. The drive 26 is axially located directly between the motor 24 and the positive displacement pump 28.

[0073] The drive nut 54 of the actuator 26 is connected to the rotor shaft 62 and driven by the rotor shaft 62 to rotate on a common axis CA. The drive nut 54 can be attached to the rotor shaft 62 by fasteners (e.g., bolts), adhesives, or press fits, among other options. In the example shown, a nut mounting protrusion 106 facilitates the mounting of the drive nut 54 to the rotor shaft 62. Fasteners can extend into the rotor shaft 62 through the nut mounting protrusion 106. A first axial end 120 engages with a nut shoulder 108 formed on the drive nut 54. The nut shoulder 108 is formed between the nut mounting protrusion 106 and an axial extension 110 that extends into and radially overlaps the rotor shaft 62. A screw 56 is radially disposed within the drive nut 54. The screw 56 and the drive nut 54 are configured to be coaxial with the common axis CA.

[0074] A rolling element 104 is disposed between the screw 56 and the drive nut 54 and supports the screw 56 relative to the drive nut 54. The rolling element 104 is arranged around and along an axis coaxial with the common axis CA. The rolling element 104 circumferentially defines a receiving region in which a portion of the screw 56 is disposed throughout operation. The screw 56 extends axially beyond both ends of the receiving region. The receiving region may be cylindrical and coaxial with the common axis CA, the reciprocating axis of the fluid displacement member 34, and the rotation axis of the rotor 42. The rolling element 104 supports the screw 56 within the drive nut 54 such that a radial clearance 132 is formed between the screw 56 and the drive nut 54 and is maintained by the rolling element 104 rolling between the screw 56 and the drive nut 54. The clearance 132 prevents the screw 56 and the drive nut 54 from directly contacting each other. The rolling element 104 engages the thread 116 of the screw 56 to apply an axial driving force to the screw 56, thereby causing the screw 56 to translate axially along the common axis CA. The rolling element 104 can have any suitable configuration for supporting the drive nut 54 relative to the screw 56 and linearly driving the screw 56 due to the rotation of the drive nut 54. For example, the rolling element 104 can be a ball or an axially elongated roller. The ball can engage the threads of the nut 54 and the thread 116. The axially elongated roller can include a threaded shaft that engages the thread 116 to drive the screw 56. The rolling elements 104 are arranged circumferentially about a common axis CA.

[0075] In the example shown, screw 56 is configured to reciprocate along a common axis CA during operation. Rotation of the drive nut 54 causes the rolling element 104 to apply an axial driving force to screw 56 to linearly drive screw 56 along the common axis CA. Screw 56 provides a linear output from driver 26 to positive displacement pump 28. Although screw 56 is described as reciprocating along the common axis CA, it should be understood that in some examples, screw 56 is configured to rotate along the common axis CA to drive displacement of linear fluid displacement member 34. For example, a nut may be attached to screw 56 to allow linear displacement along screw 56 due to rotation of screw 56. In such examples, screw 56 may be directly connected to the rotor shaft or formed as part of rotor shaft 62. Furthermore, although screw 56 is shown external to motor 24 in this embodiment, in some embodiments screw 56 may be translated into motor 24. For example, the drive nut 54 and rolling element 104 may be radially inward of the rotor 42 (particularly in embodiments where the rotor 42 resides within and rotates within the stator 44) to drive the screw 56 extending through the hollow core of the motor 24 (the hollow core extends through the rotor 42 and is coaxial with the rotor 42 and the common axis CA). In another embodiment, while the drive nut 54 and rolling element 104 are not radially overlapped by the rotor 42, the screw 56 extends into the hollow core of the motor 24 (e.g., the end of the screw is backed up, translated through, and located within the hollow core of the motor 24). Thus, in some examples, the linear displacement element of the driver 26 (e.g., the screw 56) radially overlaps with the motor 24 during at least a portion of the pump cycle, while the rotating component of the driver (e.g., the nut 54) does not radially overlap with the motor 24. In each case, both the hollow core and the screw 56 are coaxial with the common axis CA.

[0076] Pump shaft 68 is connected to screw 56 and fluid displacement member 34. Pump shaft 68 is coaxially arranged with motor 24 and fluid displacement member 34 on a common axis CA. Pump shaft 68 is coaxially arranged with screw 56, drive 54 and rotor shaft 62 on the common axis CA. Pump shaft 68 is connected to screw 56 to reciprocate along the common axis CA. In the example shown, pump shaft 68 reciprocates with screw 56. It should be understood that in examples where screw 56 rotates instead of reciprocates, pump shaft 68 may be connected to screw 56 to reciprocate along screw 56.

[0077] Pump shaft 68 is connected to fluid displacement member 34 to drive the reciprocating motion of fluid displacement member 34. Therefore, screw 56 and pump shaft 68 can be considered as forming a linear displacement element of actuator 26. Pump shaft 68 extends into bore 118 within screw 56. Pump shaft 68 can be connected to screw 56 in any desired manner, such as via interface threads, pins, press fits, adhesives, or spring locks, among other options. Although pump shaft 68 and screw 56 are described as being formed separately, it should be understood that screw 56 and pump shaft 68 can be formed as a single component. In some examples, fluid displacement member 34 can be directly connected to screw 56, and timing member 70 can also be mounted to screw 56.

[0078] The timing member 70 is mounted on and supported by the pump shaft 68. The pump shaft 68 and the timing member 70 can be considered to form a timing assembly to prevent the linear displacement element of the actuator 26 from rotating about a common axis CA. In the example shown, the timing assembly prevents the screw 56 from rotating to cause the screw 56 to undergo linear displacement. The pump shaft 68 forms a support for the timing assembly because it supports the timing member 70. The timing member 70 reciprocates together with the screw 56 and the pump shaft 68. The timing member 70 is timed and engages with the body 72, thereby preventing the timing assembly from rotating about the common axis CA. For example, a protrusion formed on one of the timing member 70 and the body 72 can engage with a groove formed on the other of the timing member 70 and the body 72. Thus, the timing member 70 prevents the screw 56 from rotating about the common axis CA, thereby facilitating translation of the screw 56 along the common axis CA. In some examples, the outer surface of the timing member 70 fits tightly with the body 72 to provide a sliding seal at the interface between the timing member 70 and the body 72. The sliding sealing interface prevents the migration of dust and other contaminants through the body 72. In the example where the screw 56 rotates about the common axis CA, the timing component 70 can be associated with a nut that is configured to translate along the screw 56 to prevent the nut from rotating about the common axis CA.

[0079] Sensor 66 is configured to sense the end of a pump stroke along a first axial direction AD1 and / or the linear and / or rotational position of a moving element of the pump device 12. A first transducer component 126 may be mounted in a bore in the pump frame 22, and a second transducer component 128 may be mounted in a bore in the pump shaft 68, among other options. Sensor 66 may generate data based on the position of the linear and / or rotational displacement element and provide the data to a controller 29 of the motor 24. In the example shown, sensor 66 is configured to generate a date indicating when the linear displacement element is at the end of a downward stroke, which may be associated with the original position. In some examples, the motor 24 returns to its original position upon energization. For example, rotor 42 may be driven in a first rotational direction associated with the downward stroke until the first transducer component 126 senses the second transducer component 128, indicating the end of the downward stroke. Rotor 42 may then be controlled to rotate a set number of revolutions associated with the stroke to induce subsequent upward and downward strokes. In some examples, motor 24 repositions during operation to prevent creep, such as after a predetermined number of pump cycles or pump strokes. In some examples, sensors may be integrated into motor 24 to sense the angular position of rotor 42 for control and signal timing purposes. For example, a second sensor associated with motor 24 may generate data on the rotation of rotor 42 and provide that data to controller 29. The first transducer component 126 and the second transducer component 128 can have any desired configuration. For example, one of the first transducer component 126 and the second transducer component 128 may be a magnet, while the other may be a reed switch sensitive to the magnetic field generated by the magnet. The magnet component may be mounted on either pump frame 22 and pump shaft 68, and the magnetic field sensor may be mounted on the other component.

[0080] A positive displacement pump 28 is mounted on a pump frame 22 and positioned on a common axis CA. More specifically, a pump body 36 is mounted on the end of the pump frame 22 opposite to the motor 24. The pump body 36 is fixedly mounted on the pump frame 22. The pump body 36 is fixed to the pump frame 22 such that it remains stationary during operation and does not move relative to the common axis CA. The pump body 36 can be cylindrical about an axis coaxial with the common axis CA. Thus, the pump body 36 can extend along an axis coaxial with the rotation axis of the rotor 42.

[0081] A fluid displacement member 34 is at least partially disposed within the pump body 36. In the example shown, the fluid displacement member 34 extends along an axis coaxial with the common axis CA. In the example shown, the fluid displacement member 34 is a piston configured to pump fluid by reciprocating along the common axis CA. However, it should be understood that the fluid displacement member 34 can have any desired configuration suitable for pumping while being coaxial with the common axis CA. For example, the fluid displacement member 34 can be a diaphragm with a center, which is disposed and configured to reciprocate along the common axis CA. Although the fluid displacement member 34 is described as reciprocating along the common axis CA in this example, it should be understood that some examples of the fluid displacement member 34 can rotate on the common axis CA without reciprocating.

[0082] The fluid displacement member 34 extends axially between a first end 134 and a second end 136. The first end 134 of the fluid displacement member 34 is connected to a linear displacement drive element of the pump device 12. In the example shown, the first end 134 of the fluid displacement member 34 is the axial end of the pump shaft 68 opposite to the screw 56, directly connected. In the example shown, the first end 134 of the fluid displacement member 34 extends into the pump shaft 68. The first end 134 is secured to the pump shaft 68 such that the fluid displacement member 34 reciprocates with the screw 56 and the pump shaft 68 along a common axis CA. The first end 134 and the pump shaft 68 can be connected in any desired manner. For example, a pin can extend through the first axial end 134 and through the pump shaft 68 to secure the fluid displacement member 34 to the pump shaft 68. Although the fluid displacement member 34 is described as being directly connected to the pump shaft 68, it should be understood that the fluid displacement member 34 can be directly connected to other linear displacement elements of the drive 26. In some examples, the fluid displacement element 34 can be directly connected to the screw 56.

[0083] Positive displacement pump 28 is statically connected to pump frame 22 via a connection between pump body 36 and body 72. This static connection holds pump body 36 in a set position along a common axis CA. The static connection prevents movement of pump body 36 relative to the common axis CA. For example, the static connection prevents linear movement along the common axis CA or rotational movement about the common axis CA. Positive displacement pump 28 is dynamically connected to motor 24 via a connection between fluid displacement member 34 and driver 26. This dynamic connection allows movement of fluid displacement member 34 relative to the common axis CA. For example, the dynamic connection causes linear movement along the common axis CA or rotational movement about the common axis CA, depending on the configuration of positive displacement pump 28.

[0084] Check valve 58a is a one-way valve supported by pump body 36. Check valve 58b is a one-way valve disposed in fluid displacement member 34 for reciprocating motion with fluid displacement member 34. In the example shown, check valve 58b is disposed at the second axial end 136 of fluid displacement member 34. The second positive displacement pump 28 can be a double positive displacement pump because the positive displacement pump 28 outputs fluid during both its upward stroke in the second axial direction AD2 and its downward stroke in the first axial direction AD1. Check valve 58a can be coaxial with common axis CA. More specifically, both the ball and annular seat of check valve 58a can be coaxial with common axis CA. Check valve 58b can be coaxial with common axis CA. More specifically, both the ball and annular seat of check valve 58b can be coaxial with common axis CA.

[0085] Dynamic seals 124a and 124b are disposed at the interface between the fluid displacement member 34 and the pump body 36. Dynamic seal 124a divides the interior of the pump body 36 into an upstream chamber and a downstream chamber. Dynamic seal 124a can be mounted to the fluid displacement member 34 to move with it, or it can be stationary relative to the pump body 36, allowing the fluid displacement member 34 to move relative to dynamic seal 124a. In the example shown, the fluid displacement member 34 exits the pump body 36 via dynamic seal 124b. Dynamic seal 124b is supported by the pump body 36 and remains stationary relative to it, allowing the fluid displacement member 34 to move relative to dynamic seal 124b. Dynamic seals 124a and 124b can be formed from a stack of sealing rings. Dynamic seals 124a and 124b are coaxially disposed on a common axis CA, and are therefore coaxial with the rotation axis of the rotor 42 and the reciprocating axis of the fluid displacement member 34.

[0086] An exemplary pump cycle including a downward stroke and an upward stroke is described by way of example. During operation, power is supplied to stator 44 to drive rotor 42 to rotate about a common axis CA. Rotor 42 rotates about the common axis CA in a first direction of rotation (e.g., one of clockwise and counterclockwise) and rotor shaft 62 rotates simultaneously due to the connection between rotor 42 and rotor shaft 62. Due to the connection between rotor shaft 62 and drive nut 54, rotor shaft 62 rotates on the common axis CA and powers drive 26.

[0087] The drive nut 54 rotates on the common axis CA, causing the rolling element 104 to apply an axial driving force to the screw 56 in the second axial direction AD2, thereby linearly driving the screw 56 along the common axis CA. The screw 56 is linearly driven along the second axial direction AD2 and toward the motor 24. In some examples, a portion of the screw 56 extends into a portion of the motor 24 and axially overlaps with that portion. In such examples, the amount of axial overlap increases as the screw 56 displaces along the second axial direction AD2. The screw 56 pulls the fluid displacement member 34 along the common axis CA and the second axial direction AD2 through an upward stroke. During the upward stroke, check valve 58a opens and check valve 58b closes. The volume of the upstream chamber formed between the fluid displacement member 34 and the check valve 58a increases, and the volume of the downstream chamber on the opposite axial side of the dynamic interface between the fluid displacement member 34 and the dynamic seal 124a decreases. Fluid is drawn into the upstream chamber through check valve 58a, while simultaneously being driven downstream from the downstream chamber of positive displacement pump 28.

[0088] After completing the upward stroke, rotor 42 is driven in a second rotational direction opposite to the first rotational direction (e.g., another of clockwise and counterclockwise directions). Rotor 42 drives the rotation of rotor shaft 62, which in turn drives the rotation of drive nut 54. Rolling element 104 applies an axial driving force to screw 56 along a first axial direction AD1 to linearly drive screw 56 along a common axis CA. Screw 56 drives pump shaft 68 and thus drives fluid displacement member 34 through a downward stroke along the common axis CA and the first axial direction AD1. During the downward stroke, check valve 58a is closed and check valve 58b is open. Fluid is driven from the upstream chamber to the downstream chamber through check valve 58b. Fluid is driven downstream from positive displacement pump 28. Sensor 66 can sense the end of the downward stroke and provide this data to controller 29. In the example shown, positive displacement pump 28 outputs fluid during both the upward and downward strokes.

[0089] Axial forces are generated and experienced during pumping. Bearing assembly 64 allows rotational motion from motor 24 to be transmitted within driver 26 while preventing some or all of the axial forces generated by positive displacement pump 28 from being transmitted to rotor 42. Fluid displacement member 34 moves linearly along a common axis CA and experiences axial forces due to fluid resistance during reciprocating motion. Specifically, fluid displacement member 34 experiences a downward reaction force during its upward stroke and an upward reaction force during its downward stroke. Both the upward and downward reaction forces are transmitted to bearing assembly 64 via driver 26. The coaxiality of motor 24, fluid displacement member 34, and bearing assembly 64 facilitates efficient force transmission to protect motor 24 from reaction forces. Bearing assembly 64 is coaxially arranged with the reciprocating axis of fluid displacement member 34 such that the forces supplied to bearing assembly 64 are balanced around the common axis CA. Bearing assembly 64 transmits this force to pump frame 22 to isolate motor 24. This coaxiality facilitates a compact and efficient bearing arrangement.

[0090] In the example using elongated rollers, the pitch on the screw 56, drive nut 54, and possibly rolling element 104 determines the ratio of rotor 42 rotation to the linear stroke of fluid displacement member 34. The rotor 42 and drive 26 are dimensioned to provide the desired rotation-to-stroke ratio. In some examples, the rotor 42 and drive 26 are dimensioned such that one rotation of rotor 42 results in a full stroke of fluid displacement member 34 in one of the first axial directions AD1 and AD2. A full rotation in the opposite directions results in a full stroke of fluid displacement member 34 in the opposite axial directions. Thus, two rotations in opposite directions can provide a complete pump cycle of fluid displacement member 34, each pump cycle comprising one stroke in each axial direction (e.g., an upward stroke and a downward stroke). Therefore, pump device 12 can provide a 1:1 ratio between rotor 42 rotation and pump stroke.

[0091] However, it is understood that the dimensions of rotor 42 and drive 26 can be designed to provide any desired speed-to-stroke ratio. Pump device 12 can be configured to provide any desired speed-to-stroke ratio. In some examples, pump device 12 provides a speed-to-stroke ratio of up to about 4:1. It should be understood that other maximum speed-to-stroke ratios are possible, such as about 1:1, 2:1, 3:1, or 5:1, among other options. In some examples, pump device 12 can provide a speed-to-stroke ratio between about 0.25:1 and 7:1. It should be understood that any range discussed can be a range that includes endpoints, such that boundary values ​​are included within that range. It should also be understood that each of the ranges discussed can differ from the specified range while still falling within the scope of this disclosure.

[0092] It should also be understood that controller 29 can control the operation of motor 24 such that the actual stroke length is dynamic and can vary during operation. Controller 29 can vary the stroke length between a downward stroke and an upward stroke. In some examples, controller 29 is configured to control the operation of motor 24 between a maximum stroke length and a minimum stroke length.

[0093] Motor 24 and drive 26 can be configured to rotate fluid displacement member 34 by at least about 6.35 mm (about 0.25 inches) per rotor 42. Rotor 42 rotates 8.9–30.5 mm (about 0.35–1.2 inches) per revolution. In some examples, motor 24 and drive 26 are configured to move fluid displacement member 34 between about 8.9–11.4 mm (about 0.35–0.45 inches). In some examples, motor 24 and drive 26 are configured to move fluid displacement member 34 between about 19–21.6 mm (about 0.75–0.85 inches). In some examples, motor 24 and drive 26 are configured to move fluid displacement member 34 between about 24.1–26.7 mm (about 0.95–1.05 inches). The axial displacement of rotor 42 per revolution provided by pumping device 12 contributes to precise control and rapid response during pumping. The axial displacement of rotor 42 per revolution facilitates rapid transitions between pump strokes, minimizes the time when fluid displacement component 34 is not moving, provides more efficient pumping, and reduces wear on components of pump equipment 12.

[0094] Pumping device 12 is configured to pump based on a speed-to-displacement ratio. More specifically, motor 24 and drive 26 are configured to provide a desired speed-to-displacement ratio, measured in inches, between the speed of rotor 42 and the linear travel distance of fluid displacement member 34 for each revolution of rotor 42. In some examples, the speed-to-displacement ratio (rpm) is less than about 4:1. In some examples, the speed-to-displacement ratio is between about 0.85:1 and 3.25:1. In some examples, the speed-to-displacement ratio is between about 1:1 and 3:1. In some examples, the speed-to-displacement ratio is between about 1:1 and 2.75:1. In some examples, the speed-to-displacement ratio is about 1:1 to 2.55:1. In some examples, the speed-to-displacement ratio is between about 1:1 and 1.3:1. In some examples, the speed-to-displacement ratio is between about 0.9:1 and 1.1:1. In some examples, the speed-to-displacement ratio is between approximately 2.4:1 and 2.6:1. Compared to other electric pumps, such as crank-driven pumps that require reduction gears to generate sufficient pumping torque and typically have a speed-to-displacement ratio of approximately 8:1 or higher, the lower speed-to-displacement ratio provided by pump unit 12 facilitates more efficient pumping, produces less wear, and provides a faster response to changes in stroke direction. The rotor 42 can be driven at a lower speed to produce the same linear velocity, thereby generating less heat during operation.

[0095] Pump assembly 12 offers significant advantages. The motor 24 and fluid displacement member 34 are coaxially arranged on a common axis CA, facilitating a compact and lightweight pumping arrangement. Compared to pump arrangements including gear reduction gears, the coaxial arrangement of the motor 24 and fluid displacement member 34 allows for rapid response and control. The motor 24 can generate high torque at low speeds and eliminates the need for reduction gears to drive the displacement of the fluid displacement member 34. The motor 24 provides rotational power directly to the driver 26, and the driver 26 provides linear power directly to the fluid displacement member 34. The coaxial arrangement of the rotating and reciprocating components on the common axis CA facilitates efficient force transmission, even under load on the common axis CA, preventing wear and increasing the service life of pump assembly 12.

[0096] Each rotating component of pump assembly 12 (e.g., rotor 42, rotor shaft 62, and drive nut 54) is connected together to rotate together at a common rotational speed. Each axial displacement component of pump assembly 12 (e.g., screw 56, pump shaft 68, and fluid displacement member 34) is connected together to displace linearly at a common axial speed. This common speed facilitates rapid response and overturning because the rotational output does not need to be accelerated or otherwise altered via a reduction gear train. Thus, pump assembly 12 provides a compact, lightweight assembly suitable for pumping fluids under high pressure.

[0097] Figure 4A It is a perspective view showing the components of motor 24 in three dimensions. Figure 4B This is a three-dimensional diagram of stator 44. It will be discussed together. Figure 4A and Figure 4B Motor 24 includes a stator 44 surrounded by a rotor 42. An array 46 of permanent magnets 46 of the rotor 42 is shown. The permanent magnet array 46 includes magnets 138 and concentrators 140. The stator 44 includes phase assemblies 50a-50c (collectively referred to herein as "phase assemblies 50" or "multiple phase assemblies 50"). Phase assembly 50a includes a pair of flux loops 142a, 142b; an axial return section 144; and a coil 52. Phase assembly 50b includes a pair of flux loops 142c, 142d; an axial return section 144; and a coil 52. Phase assembly 50c includes a pair of flux loops 142e, 142f; an axial return section 144; and a coil 52. Each flux loop 142a-142f (collectively referred to herein as "flux loop 142" or "multiple flux loops 142") includes a circular spike array 146a-146f (collectively referred to herein as "circular spike array 146" or "multiple circular spike arrays 146"). Each flux loop 142a-142f includes a stack 148, a branch 150, a trunk 152, a hoop 154, and multiple spikes 156.

[0098] Motor 24 is positioned along a common axis CA. More specifically, motor 24 has a cylindrical profile coaxial with the common axis CA. Each of stator 44 and rotor 42 also has a cylindrical profile coaxial with the common axis CA. Rotor 42 is driven by stator 44 to rotate coaxially about the common axis CA. Although in this embodiment, rotor 42 rotates circumferentially around stator 44 on the common axis CA, in alternative embodiments, rotor 42 may alternatively be located inside stator 44. Whether rotor 42 is around or inside stator 44, the operating principle of motor 24 and the structure of rotor 42 and stator 44 can be similar. Therefore, although the following discussion refers to an embodiment where rotor 42 rotates about stator 44, these teachings also apply to embodiments where rotor 42 rotates inside stator 44.

[0099] In the illustrated embodiment, the rotor 42 includes a permanent magnet array 46. The permanent magnet array 46 includes a plurality of permanent magnets 138. The plurality of magnets 138 are arranged in a ring around a common axis CA. More specifically, the tubular array of the plurality of magnets 138 is coaxial with the common axis CA. The plurality of magnets 138 are arranged circumferentially around the common axis CA. The plurality of magnets 138 are arranged circumferentially around the stator 44.

[0100] like Figure 4AAs shown, each magnet 138 has a major axis LA, which is axially oriented (parallel to the common axis CA). Each magnet 138 also has a minor axis SA, as shown... Figure 4A As shown, the short axis SA is orthogonal to the long axis LA and tangent to the rotor 42. The short axis SA of each magnet 138 may be tangent to a circle centered on a common axis CA. Each magnet 138 has permanent magnet poles—a north pole and a south pole—that are circumferentially oriented. More specifically, each magnet 138 has a north pole at one end of the short axis SA and a south pole at the opposite end of the short axis SA. Each of the north and south poles extends the length of the long axis LA such that the north and south poles are separated along the axial interface of the long axis LA. The north and south poles of each magnet 138 are not axially oriented in the manner that magnets are typically divided into north and south poles at opposite ends of their long axis LA. In the illustrated embodiment, although the plurality of magnets 138 are arranged in a ring around the stator 44, as described above, the plurality of magnets 138 may be arranged in a ring within the stator 44. The stator 44 may not contain any permanent magnets, but rather electromagnets that, as further described herein, generate a magnetic field by coils 52 when energized. Similarly, rotor 42 may consist only of permanent magnets and not any electromagnets.

[0101] The rotor 42 also includes a plurality of concentrators 140. The plurality of concentrators 140 are interleaved with a plurality of magnets 138. Thus, no magnet 138 physically contacts another magnet 138, and no magnet 138 is physically adjacent to another. However, the magnets 138 are physically secured by the plurality of concentrators 140. The plurality of concentrators 140 are axially oriented such that the major axis of each concentrator 140 is parallel to a common axis CA. The major axis of each concentrator 140 is parallel to the major axis LA of each magnet 138. Each concentrator 140 may be formed by stacked layers. The major axis of each stack is parallel to the common axis CA. Therefore, the grain of the stacked layers is axially oriented.

[0102] Each magnet 138 extends parallel to a common axis. Each magnet 138 may span multiple phases of the stator 44 and interact magnetically with them. For example, each magnet 138 may radially overlap with multiple annular arrays of multiple coils 52 and spikes 156. Each concentrator 140 extends parallel to a common axis. Each concentrator 140 may span multiple phases of the stator 44 and interact magnetically with them. For example, each concentrator 140 may radially overlap with multiple annular arrays of multiple coils 52 and spikes 156.

[0103] The multilayer can be made of a material that is very easily polarized under the influence of the magnetic field generated by the coil. This material is typically ferromagnetic. Ferromagnetic materials can be metals such as iron or iron alloys such as steel. More specifically, the multilayer can be made of silicon steel and other options. Ferromagnetic materials can also be ceramics doped or embedded with ferromagnetic elements.

[0104] The stator 44 includes a plurality of spikes 156. Each spike 156 projects toward the rotor 42. For example, each spike 156 projects radially (orthogonally) toward the rotor 42 relative to a common axis CA. In this embodiment, each spike 156 is configured to narrow toward the rotor 42 to concentrate a finite portion of the magnetic flux toward the rotor 42. More specifically, the circumferential width of each spike 156 narrows as it extends radially toward the rotor 42 relative to the stator 44. In some embodiments, the spike 156 may not narrow toward the rotor 42, but magnetic flux may still be concentrated toward the rotor 42. In this embodiment, the spikes 156 project outward from the common axis CA because the rotor 42 is positioned radially outward from the stator 44. However, in an alternative embodiment with an inner rotor 42, the spikes 156 project inward toward this rotor 42 and toward the common axis CA. The plurality of spikes 156 are arranged in a tubular profile. More specifically, multiple spikes 156 are arranged in a ring around a common axis CA and axially along the common axis CA. Thus, the stator 44 includes multiple circular spike arrays 146a-146f. Figure 4B The embodiment shows six circular spike arrays 146a-146f arranged along a common axis CA. Each circular spike array 146a-146f is coaxial with the common axis CA. The multiple circular spike arrays 146a-146f define a cylinder coaxial with the common axis CA. The spikes 156 do not need to protrude into the air gap from other physical components of the stator 44. Instead, the spikes 156 can be partially or completely embedded in a potting compound such as epoxy resin. For example, the stator 156 can have a cylindrical exterior, wherein the spikes 156 are located internally and / or exposed on the cylindrical outer surface, but the spikes 156 still function to concentrate electromagnetic flux relative to the surrounding potting material.

[0105] In this embodiment, the circular spike arrays 146a-146f are each part of a plurality of flux loops 142a-146f. Each flux loop 142 supports all the spikes 156 of its corresponding circular spike array 146. For example, flux loop 142a supports all the spikes 156 of circular spike array 146a. Each flux loop 142 is at least partially formed by lamination. Each flux loop 142a-146f may be a continuous lamination or formed by a plurality of laminations arranged around a common axis CA. In this embodiment, each flux loop 142a-146f includes a hoop 154, a plurality of main stems 152 extending radially relative to the hoop 154, and a plurality of branches 150 supported by the plurality of main stems 152.

[0106] For each flux loop 142, a hoop 154 ​​extends as a loop completely around the common axis CA. A trunk 152 extends radially from the hoop 154 ​​toward the rotor 42. In the example shown, the trunk 152 extends radially away from the common axis CA because the motor 24 is an outer rotor. A branch 150 is supported by the trunk 152. The branch 150 is located at the radial end of the trunk 152 opposite to the hoop 154. The branch 150 extends circumferentially from the trunk 152 in a first circumferential direction (e.g., one of clockwise and counterclockwise) around the common axis CA and in a second circumferential direction (e.g., the other of clockwise and counterclockwise) around the common axis CA. Spikes 156 are formed on the radial side of the branch 150 opposite to the trunk 152.

[0107] In some other embodiments, the flux ring 142 does not include the hoop 154 ​​and / or the trunk 152, in which case the branches 150 are directly connected and / or supported by other structures, such as epoxy resin or other potting compounds. In some embodiments, multiple stacked pieces are assembled together to form each circular flux ring 142 and / or circular spike array 146, for example by multiple arcuate portions assembled together.

[0108] Each hoop 154 ​​is coaxial with the common axis CA. Whether assembled from discrete stacked components, each supporting multiple, but not all, of the spikes 156 of the circular spike array 146, or formed from a continuous stack supporting all the spikes 156 of the circular spike array 146, the circular spike array 146a-146f is supported by flux rings 142a-142f, which allow magnetic flux to flow between circumferentially adjacent spikes 156. Multiple flux rings 142a-142f are arranged along and around the common axis CA. Each flux ring 142a-142f is coaxial with the common axis CA. The stack 148 forming the flux rings 142a-142f forms at least a portion of the spike 156. The spike 156 in this embodiment, as further described herein, includes a spike body 158 formed by the stack and a powder metal end portion 160 formed by powder metal. However, it should be understood that in various other embodiments, the stack 148 may fully form the spikes 156.

[0109] In this embodiment, each spike 156 includes a powdered metal end portion 160, which may be ideal in some embodiments (due to the lack of directional texture in powdered metal), but various embodiments are not limited thereto, and each spike 156 may not include a powdered metal component. Therefore, each spike 156 may be partially or entirely formed by a stack, for example, by a stack 148 of its associated flux ring 142. As shown, a plurality of circumferentially adjacent spikes 156 belonging to a common flux ring 142 are formed by a single common stack 148. More specifically, in the illustrated embodiment, the spike body 158 of a plurality of circumferentially adjacent spikes 156 of the same flux ring 142 is formed by a single stack 148.

[0110] Each spike 156 can be contiguous with the branch 150, trunk 152, and / or hoop 154 ​​of its flux loop 142. Thus, the spike 156, branch 150, trunk 152, and / or hoop 154 ​​of a single flux loop 142 can be formed by a single or multiple stacked members. Each spike 156 of the spike array 146 can thus be formed by a common stacked member. In the illustrated embodiment, the stacked members 148 forming flux loops 142a-142f are contiguous. Thus, the stacked portion of each flux loop 142a-142f is formed by contiguous stacks. The spikes 156, branches 150, trunk 152, and / or hoop 154 ​​can have a laminate grain extending radially (e.g., orthogonal) relative to a common axis CA. This laminate grain can be radially oriented only.

[0111] like Figure 4BAs shown, the stator 44 is formed by an array of phase components 50a-50c. The phase components 50a-50c are arranged along a common axis CA. Each phase component 50a-50c includes a pair of circular spike arrays 146a-146b, 146c-146d, and 146e-146f. Therefore, phase component 50a includes paired circular spike arrays 146a and 146b; phase component 50b includes paired circular spike arrays 146c and 146d; and phase component 50c includes paired circular spike arrays 146e and 146f. In this embodiment, each phase component 50a-50c includes a pair of flux loops 142a-142b, 142c-142d, and 142e-142f. Each pair of circular spike arrays 146a-146b, 146c-146d, and 146e-146f is connected by an axial return section 144. Each pair of flux rings 142a-142b, 142c-142d, and 142e-142f is connected by an axial return section 144.

[0112] Each phase assembly 50 includes a coil 52 axially disposed between pairs of flux loops 142 of the phase assembly 50. The coil 52 extends circumferentially about a common axis CA such that the common axis CA extends through the loop formed by each coil 52. The coil 52 is axially disposed between the stacked portions of each phase assembly 50. Each coil 52 is thus enclosed by the stacked layers.

[0113] Axial return sections 144 extend between and connect pairs of flux loops 142 to form phase assembly 50. The axial return sections 144 are arranged around a common axis CA and form a circular array for each phase assembly 50. The axial return sections 144 are arranged on the radial side of coil 52 opposite to rotor 42. The axial return sections 144 are also arranged on the radial side of coil 52 opposite to permanent magnet array 46. The array of axial return sections 144 defines a cylinder through which the common axis CA extends. The axial return sections 144 are arranged on the radial side of branch 150 opposite to spike 156. The axial return sections 144 can directly contact the stack of each flux loop 142 of phase assembly 50. For example, each axial return section 144 can directly contact the radial side of each branch 150 opposite to spike 156. In the example shown, the axial return section 144 directly contacts the radially inner side of each branch 150 because the motor 24 is of the external rotor type.

[0114] Each axial return portion 144 is formed by a stack of layers having an axial (i.e., parallel to the common axis CA) texture orientation. The texture of the stack of axial return portions 144 may be axial only. Therefore, the texture of the stack of axial return portions 144 may be orthogonal to the texture of the stack forming the flux loops 142. Thus, the motor 24 may include one or more axially oriented arrays of stacks arranged around the common axis CA. One or more axially oriented arrays of stacks define cylinders coaxial with and therefore coaxial with each other to the common axis CA. As further explained herein, the axial return portions 144 conduct electromagnetic flux between each of the pair of flux loops 142 forming the phase assembly 50. In the example shown, the first array of the axial return section 144 conducts electromagnetic flux between pairs of flux rings 142a-142b; the second array of the axial return section 144 conducts electromagnetic flux between pairs of flux rings 142c-142d; and the third array of the axial return section conducts electromagnetic flux between pairs of flux rings 142e-142f. The axial return section 144 conducts electromagnetic flux between pairs of flux rings 142 in each phase assembly 50. Similarly, the axial return section 144 conducts electromagnetic flux between each pair of circular spike arrays 146a-146b, 146c-146d, and 146e-146f. Also, the axial return section 144 conducts electromagnetic flux between axially adjacent branches 150 of the pairs of flux rings 142. As further explained herein, the spikes 156 of the paired flux loops 142a-142b, 142c-142d, 142e-142f and thus the paired array of circular spikes 146a-146b, 146c-146d, 146d-146f form multiple flux loops through the stator 44, which magnetically act on the magnets 138 of the rotor 42 to cause the rotor 34 to rotate relative to the stator 44.

[0115] The nearest flux loop 142 and / or stack 148 and / or spike 156 (or other stacked structures that guide magnetic flux to magnet 138) along the common axis CA to the displacement member 34 (and the pumping chamber(s) of the positive displacement pump 28, and the body 36 of the positive displacement pump 28) is axially closer than the nearest coil 52 along the common axis CA. This is partly because the coils do not have end turns extending axially relative to the motor 24, as discussed in more detail below.

[0116] Figure 5A This is a 3D view of phase component 50a. Figure 5B This is a perspective view of phase component 50a, in which the flux ring 142a has been removed for clarity. It will be discussed together. Figure 5A and Figure 5B Although phase component 50a is shown and discussed in more detail, it should be understood that other phase components 50b, 50c (in...) Figure 4B(Best visible in the middle) They can be identical in structure and function, the only difference being that the signals transmitted by the coils 52 of the phase assemblies 50a-50c are out of phase relative to each other. Furthermore, the phase assemblies 50a-50c can be rotated relative to each other about a common axis CA to form a stator 44. Flux ring 142a includes a circular spike array 146a, branches 150a, a trunk 152a, a hoop 154a, and spikes 156a. Flux ring 142b includes a circular spike array 146b, branches 150b, a trunk 152b, a hoop 154b, and spikes 156b.

[0117] Phase assembly 50a is formed by a pair of flux loops 142a, 142b, with coil 52 axially sandwiched between the pair of flux loops 142a-142b. Each coil 52 is a wire (typically copper) winding around a common axis CA. Thus, each coil 52 can be a continuous winding with 20, 30, 40, 50, 100 or fewer turns around the common axis CA. In some embodiments, a strip is wound instead of wire. Each coil 52 has two terminal wires 162a, 162b, which represent the ends of the circuitry of each coil 52. Figure 5B The wire ends 162a and 162b of coil 52 are shown in the best view. They are used to transmit AC signals through coil 52, which can be electrically connected to controller 29.

[0118] Coil 52 radially overlaps with the spikes 156a, 156b of phase assembly 50a because a portion of each of the spikes 156a, 156b protrudes axially along a common axis CA. Therefore, a radial line extending from the common axis CA can pass through each of the coils 52 and a portion of the spike 156 of phase assembly 50. The radial line can extend through the axial return portion 144, the coil 52, and a portion of the spike 156. In the example shown, the powder metal end portion 160 extends axially over the coil 52. Therefore, a radial line extending from the common axis CA can extend through the stack (e.g., the stack of the axial return portion 144), the wire (e.g., the coil 52), and the powder metal (e.g., the powder metal of the powder metal end portion 160). In some other embodiments, the spike 156 does not protrude axially but only radially (towards or away from the common axis CA).

[0119] Coil 52 is directly disposed between pairs of flux loops 142a and 142b. Coil 52 is disposed within the axial gap formed between pairs of flux loops 142a and 142b. More specifically, coil 52 is directly located between the stack forming flux loop 142a and the stack forming flux loop 142b. At least a portion of coil 52 is directly located between opposing branches 150a and 150b of pairs of flux loops 142a and 142b. At least a portion of coil 52 is directly located between portions of each pair of spikes 156a and 156b of pairs of circular spike arrays 146a and 146b (e.g., spike 156a of spike array 146a and spike 156b of spike array 146b). Coil 52 is directly axially located between the portions of pairs of circular spike arrays 146a and 146b formed by the stacks. Therefore, coil 52 is axially supported / enclosed by the stacks.

[0120] Coil 52 radially overlaps with axial return portion 144. In this particular embodiment, coil 52 is radially sandwiched between portions of axial return portion 144 and spikes 156a, 156b, since spikes 156a, 156b each have axially projecting portions. Therefore, coil 52 is disposed within an annular chamber coaxial with the common axis CA and defined by axial return portion 144 and flux loops 142a, 142b. In the illustrated example, three of the four sides of the annular chamber (e.g., two axial sides and one radial side) are formed by lamination. In the illustrated example, one of the four sides of the annular chamber is formed by a powder metal component (e.g., the powder metal end portion 160 of spikes 156a, 156b). However, it should be understood that some examples include an annular chamber with all four sides defined by lamination. In some examples, the annular chamber may have three sides, for example, where spikes 156a, 156b do not include axially extending components.

[0121] Figure 6A and Figure 6B It demonstrates how to form a flux loop by using the flux-paired spikes in spikes 156a and 156b. Figure 6C Detailed views of spikes 156a, 156b, representing the flux pairing of the phase assembly 50a interacting with the permanent magnet array 46 of the rotor 42, are shown. These will be discussed together. Figures 6A-6C The flux-paired spikes refer to the nearest spike pair 156 of the relative circular spike array 146 of phase assembly 50 (e.g., the nearest spike pair 156a, 156b of the relative circular spike arrays 146a, 146b of phase assembly 50a). Although spikes 156a, 156b are in Figures 6A-6CThe spikes are highlighted as flux-paired spikes in the spikes, but it should be understood that these are examples and all spikes 156a, 156b of the flux loops 142a, 142b are similarly flux-paired through the circular spike array 146a, 146b.

[0122] Each spike 156a is part of a similar flux loop with its corresponding flux-paired spike 156b. The flux-paired spikes 156a, 156b are typically axially paired with the spikes 156a, 156b of the opposing circular spike arrays 146a, 146b, rather than circumferentially paired with adjacent spikes 156a, 156b of the same circular spike arrays 146a, 146b, because the spikes 156a of all circular spike arrays 146a will have the same polarity at any given time, while all spikes 156b of the opposing circular spike arrays 146b of the same phase component 50a will have opposite polarities at any given time. More specifically, each spike 156a of the circular spike array 146a is flux-paired with the nearest spike 156b of the circular spike array 156b on the other axial side of the coil 52. For example... Figure 6A and Figure 6B As shown, the spikes 156a and 156b, which are paired by magnetic flux, form a magnetic flux loop, which polarizes the spikes 156a and 156b—north-polarized and south-polarized, respectively.

[0123] Magnetic flux is generated by coil 52. Specifically, an AC signal passes through each coil 52, which rapidly establishes and disrupts the magnetic field because the current of the AC signal passing through coil 52 is reversed. As shown, the flux-concentrating material of the flux loops 142a, 142b and the axial return portion 144 surrounds at least three sides of coil 52. Figure 6A and Figure 6B The diagram shows the layered texture of the flux-concentrating material. Typically, the flux flows along the layering direction with the texture because flux usually flows along the path of highest permeability, and there is significant resistance to flux jumping from one layer to another. The layered texture of the branches 150a, 150b (including the protrusions 156a, 156b excluding the powder metal end portion 160) is radially oriented, while the layered texture of the axial return portion 144 is axially oriented. Therefore, the flux flows axially through the axial return portion 144 in a U-shape and radially through the branches 150a, 150b and protrusions 156a, 156b toward the rotor 42, with the bottom of the U-shape on the side of the coil 52 opposite to the rotor 42, and the U-shaped legs facing the rotor 42. Figure 6A and Figure 6B This indicates how the AC signal is reversed and how the magnetic poles of the flux-paired spikes 156a and 156b switch.

[0124] The flux-paired spikes in spikes 156a and 156b are circumferentially offset from each other, such that spike 156a is not axially aligned with spike 156b. The ends of the flux-paired spikes 156a and 156b are not axially aligned because spike 156a is circumferentially offset from spike 156b, so the flux loop travels circumferentially between the flux-paired spikes of spikes 156a and 156b by at least a limited distance. Therefore, the accumulated flux loop including multiple flux-paired spikes 156a and 156b can flow circumferentially through spikes 156a and 156b and the axial return section 144 in a helical pattern. Note that although most of the magnetic flux flows between the flux-paired spikes 156a and 156b, the branches 150a and 150b allow the flow of magnetic flux between the spikes 156a and 156b of the same branch 150a and 150b, so that a limited amount of magnetic flux can skip the flux-paired spikes 156a and 156b and flow to the next spike 156a and 156b of the same branch 150a and 150b.

[0125] Figure 6C A detailed view is shown of the interaction between the flux-paired spikes 156a and 156b of the stator 44 and the concentrator 140 and magnet 138 of the rotor 42. The AC signal flowing through the coil 52 rapidly changes the direction of the current and thus rapidly changes the north-south polarity of the flux-paired spikes 156a and 156b. Figure 6C An example is shown where all spikes 156a of the circular spike array 146a have a north pole and all spikes 156b of the circular spike array 146b have a south pole. In the same case, spikes 156a, 156b are aligned with concentrators 140 circumferentially arranged between magnets 138. The stack of concentrators 140 does not have inherent polarity, but due to the fixed position of the concentrators 140 between the magnetic poles, the concentrators 140 effectively exhibit permanent polarization as shown. Each concentrator 140 contacts two magnets 138. Each concentrator 140 contacts the same pole of two magnets 138. For example, a concentrator 140 will contact either two south poles or two north poles. Depending on the polarity adjacent to the concentrator 140, the concentrator 140 presents alternating north and south poles on opposite sides of each magnet 138. As shown, each magnet 138 is permanently polarized to north and south poles on opposite sides of its minor axis. The staggered arrangement of magnet 138 and concentrator 140 produces concentrator 140 and magnet 138 with opposite polarization.

[0126] Concentrator 140 directs magnetic flux from magnet 138 to stator 126. The flux loop is completed in the air gap 60 between stator 44 and rotor 42. Magnetic flux from rotor 42 (specifically magnet 138) and from coils 52 (via spikes 156a, 156b) interact in air gap 152, and the resulting flux shear force forces rotor 42 to rotate. The magnetic flux of motor 24 has an orientation transverse to the axis of rotation (which is coaxial with coaxial CA). This differs from the radial flux direction of conventional AC and DC brushless motors.

[0127] The magnetic flux generated by the stator 44 and acting on the rotor 42 is constantly changing. This is due both to the positional changes of the magnet 138 and the concentrator 140 caused by the rotation of the rotor 42, and to the polarity changes of the spikes 156a and 156b caused by the changes in the AC signal passing through the coil 52. Therefore, the AC signal passing through the coil 52 is synchronized with the rotation of the rotor 42 to generate a magnetic field through the spikes 156a and 156b that corresponds in a timely manner to the concentrator 140 (which is approaching and leaving the spikes 156a and 156b), so as to simultaneously push and pull the magnet 138 of the rotor 42 to provide the force to rotate the rotor 42. More specifically, during the approach and departure of alignment, the NN and SS interfaces repel each other while the NS interfaces attract each other.

[0128] The corresponding AC signals (e.g., sinusoidal or trapezoidal) are out of phase with each other. Thus, compared to synchronous sinusoidal AC signals, magnets 138 (along their length) have more frequent peaks of magnetic flux acting on them to achieve a smoother torque distribution acting on rotor 42 along the axis of rotation of rotor 42 (which is also the common axis CA). Figure 2 , Figure 4A and Figure 4B The illustrated embodiment of motor 24 includes three phases, corresponding to three phase assemblies 50a-50c and coils 52 therein, wherein three 120-degree electrically offset sinusoidal AC signals are transmitted through coils 52. If there are two phase assemblies 50 and two coils 52, the two sinusoidal AC signals will be 180 degrees apart, or for a group of four phase assemblies 50, they will be 90 degrees apart.

[0129] Because magnet 138 is elongated and radially overlaps with multiple coils 52, each magnet 138 is electromagnetically acted upon by multiple coils 52. More specifically, in the example shown, each magnet 138 can be electromagnetically acted upon simultaneously by three coils 52 along the length of magnet 142. Thus, multiple different coils 52 can act electromagnetically on each magnet 138 simultaneously. Furthermore, throughout operation, each magnet 138 can be electromagnetically acted upon by only three coils 52 (or only two coils 52 in the two-phase motor 24 embodiment, or only four coils 52 in the four-phase motor 24 embodiment, etc.). This differs from conventional AC induction motors, where each magnet interacts with all windings of a conventional toroidal winding array around the rotor's axis of rotation. Because each magnet 138 is symmetrical along its long axis, motor 24 has multiple stator phases but a continuous rotor phase.

[0130] Traditional AC induction motors use multiple discrete coils that form a coil array extending circumferentially around the rotor's axis of rotation (see...). Figure 12A and Figure 12B Each coil represents a potential pole acting on a magnet. In a conventional AC induction motor, discrete coils arranged circumferentially around the axis of rotation are out of phase with each other. In any given situation, the discrete coils can interact with a small fraction of the magnet. The potential torque produced is proportional to the number of poles. The number of poles in such a motor is limited by the ability to mount discrete coils circumferentially around the axis of rotation within the motor. The coil windings can be made smaller, and the stator diameter can be made larger to accommodate more coils to support more poles, but this increases the size, weight, and cost of the motor, and there are still limitations. Power can also be increased when the rotor rotates at a relatively high rate, so that more coil-magnet passes through per unit time. However, this increase in power requires the motor to operate at relatively high speeds, while some applications may require low-speed output. Providing a speed reduction gear to reduce speed and increase torque to the required high torque and low speed increases cost, weight, size, and friction.

[0131] The motor 24 according to this disclosure differs from conventional AC and DC brushless motors. One aspect of the motor 24 is that it contains a relatively small number of coils 52, only three in the illustrated embodiment. Unlike conventional AC and DC brushless motors, the coils 52 are formed by loops of wire extending completely around the axis of rotation (and common axis CA) of the rotor 42. The axis of rotation (and common axis CA) of the rotor 42 extends through each loop (e.g., the center of each loop). Each coil 52 is annular, and the loops of each coil 52 are also annular, and the circular planar profiles of the coils 52 and the loops are orthogonal to the common axis CA. The wires of each coil 52 form a single coil clamp having multiple loops that overlap and contact each other to form a single coil clamp assembly. The coils 52 do not include loops that generate magnetic flux that causes the rotor 42 to rotate without the common axis CA extending through it. Unlike conventional AC induction motors where a coil is added for each pole, the branch 150 and axial return section 144 surrounding a single coil 52 direct magnetic flux to multiple spikes 156, which are flux-paired across the branch 150 to generate multiple poles. In the example shown, one coil 52 supports thirty poles for each phase assembly 50 because each example flux loop 142 includes thirty spikes 156, but fewer and more poles can be created depending on the number of spikes 156 in the circular spike array 138. Thus, activating one coil 52 will activate many poles, whereas activating one coil in some conventional AC and DC brushless motors activates only one pole. In some examples, each coil 52 may interact with each magnet 138 under a given condition. Furthermore, multiple coils 52 are arranged as part of multiple phase assemblies 50 along the axis of rotation of the rotor 42, thereby multiplying the number of poles.

[0132] The high pole number eliminates or reduces the need for reduction gears, further reducing eccentric forces and lightening weight and friction, thus allowing for a more compact arrangement of the pump unit 12. Since pumping applications are typically performed at low speeds, the high pole number allowed by this motor 24 design means that high torque can generate high fluid pressure even at low pumping speeds with little or no drive reduction, which again reduces cost, weight, friction, and package size. For at least these reasons, the motor 24 of this disclosure can generate high torque in a small package size, even at the low speeds where the pump typically operates. Therefore, drive reduction in the driver can be minimized or completely eliminated, resulting in savings in cost, size, weight, and friction.

[0133] Figure 7This is a schematic diagram of pump assembly 12'. Pump assembly 12' includes a motor 24', a driver 26, and a positive displacement pump 28'. Motor 24' is an internal rotor type, having a rotor 42' disposed within a stator 44'. Rotor 42' rotates within stator 44'. Except for the stator 44's protrusions 156 extending radially inward toward the common axis CA and toward the internal rotor 42', and the external rotor type protrusions 156 extending radially outward relative to the common axis CA and toward the external rotor 42, stator 44' is substantially similar to stator 44 (ideally as follows). Figure 5A (As shown). Except that the permanent magnet array 46 is arranged radially outside the rotor 42' relative to the rotor 42', while the permanent magnet array 46 of the outer rotor motor is arranged radially inside the outer rotor 42, the rotor 42' is substantially similar to the rotor 42 (ideally as shown). Figure 2 and Figure 5A (As shown).

[0134] In the example shown, positive displacement pump 28' includes an inlet check valve 58a and an outlet check valve 58c, which can be any desired form of check valve, such as ball valves and seat valves, among other options. Each of the inlet check valve 58a and the outlet check valve 58c is stationary relative to the common axis CA. A pumping chamber 164 is fluidly connected to each of the inlet check valve 58a and the outlet check valve 58c. The volume of pumping chamber 164 increases as the fluid displacement member 34 is axially pulled toward the motor 24', and decreases as the fluid displacement member 34 is axially driven away from the motor 24'. In the example shown, positive displacement pump 28' is a single-displacement pump that drives fluid downstream only during one of the pump strokes. However, it should be understood that positive displacement pump 28' can be similar to positive displacement pump 28 (…). Figures 1A-3C The dual-volume pump 28' enables the positive displacement pump 28' to output fluid during each stroke of the pump cycle.

[0135] Along the common axis CA, the nearest flux loop 142 and / or stack 148 and / or spike 156 (or other stacked structures that guide magnetic flux to magnet 138) to displacement member 34 (and pumping chamber 164) is positioned closer to the axial position of the volumetric pump 28' (and pumping chamber 164) than the axially nearest coil 52. This is partly because coil 52 has no axially extending end turns. Thus, pumping device 12' provides a compact and efficient pumping mechanism.

[0136] Figure 8 This is a schematic block diagram of pump device 12''. While various other embodiments mentioned herein may have a linearly reciprocating fluid displacement member 34, in this embodiment, and in various other embodiments, the fluid displacement member 34' may rotate and may reciprocate or may not reciprocate. Figure 8The pump device 12'' includes a motor 24 having a rotor 42 that rotates inside or outside a stator 44. The stator 44 includes a plurality of coils 52 (three in this embodiment, but more or fewer may be provided in various other embodiments) that generate magnetic flux through the stator 44 to drive the rotor 42. The rotor 42 rotates coaxially with a common axis CA. The fluid displacement pump 28'' includes a rotating fluid displacement member 34'. The fluid displacement member 34' may be elongated along the common axis CA. The fluid displacement member 34' may be coaxial with the common axis CA. The fluid displacement member 34' may rotate coaxially with respect to the common axis CA. The rotation of the fluid displacement member 34' can pump fluid. The rotation axis AR of the rotor 42 may be coaxial with the rotation axis AR2 of the fluid displacement member 34'.

[0137] Figure 8 The positive displacement pump 28'' can be a progressive cavity pump, a vane pump, an impeller pump, or a peristaltic pump, among other options. There may be no mechanical amplification between the rotor 42 and the rotating fluid displacement member 34'. For example, there may be no gearing between the rotor 42 and the rotating fluid displacement member 34', or there may be no gearing throughout the entire pump assembly 12''. The rotor 42 and the rotating fluid displacement member 34' can be fixed such that one rotation of the rotor 42 results in one rotation of the rotating fluid displacement member 34'.

[0138] In the case of a peristaltic pump, the rotary fluid displacement member 34' can be a rotor type that rotates within a housing containing a flexible tube. The rotor forming the fluid displacement member 34' moves along the tube to progressively and repeatedly squeeze the interior of the housing along a portion of the length of the flexible tube. As the rotary fluid displacement member 34' rotates, the rotor repeatedly initiates and releases its squeezing of the flexible tube along the length of the tube.

[0139] In the case of a vane pump, the rotating fluid displacement member 34' can be a rotor that rotates within a housing. Two vanes can project in opposite directions from the rotor forming the fluid displacement member 34'' within the housing. The vanes can be supported on one or more springs to allow the vanes to move in and out of the rotor to accommodate the internal shape of the housing. The housing can be coaxial with a common axis CA. The rotor can rotate about an axis of rotation coaxial with the common axis CA.

[0140] Figure 9This is a schematic block diagram showing a positive displacement pump 28'' as a progressive cavity pump. An internal rotor motor 24' is connected to a fluid displacement member 34' to cause pumping by the positive displacement pump 28''. In this embodiment, the rotating fluid displacement member 34' is a helical rotor 166. The helical rotor 166 rotates within a progressive cavity stator housing 168. The helical rotor 166 may include fins, as shown, for propelling or otherwise moving a liquid, such as water. An elastomer on the inner side of the progressive cavity stator housing 168 forms a series of cavities including lobes, through which the helical rotor 166 enters and exits to progressively move multiple corresponding pockets from one end of the pump to the other, through which fluid moves under pressure. The helical rotor 166 can rotate about a common axis CA. The helical rotor 166 can rotate coaxially with respect to the common axis CA. In some embodiments, the helical rotor 166 may be disposed inside a tube having a cylindrical internal profile (e.g., not a progressive cavity), or the helical rotor 166 may be fully exposed to the moving liquid medium without an outer sleeve surrounding the helical rotor 166.

[0141] As discussed herein, the device according to this disclosure can have various advantages. One advantage could be the reduction of canting of the fluid displacement components, which would otherwise lead to lateral loading and premature failure. Figure 10 A schematic diagram of a motor 24 operatively connected to pump 28 is shown. Specifically, a flux ring 142 is shown. As described and shown above, the annular array of spikes 156 ( Figure 10 (not shown in the image) is coiled ( Figure 10 (Not shown in the image) are simultaneously polarized to the same polarity, completely surrounding the flux loop 142. This is indicated by a "+" sign with respect to the flux loop 142, however, depending on the portion of the phase period, it can also be "-". Figure 10The phase assembly 50 of motor 24 is further shown. Phase assemblies 50 are labeled A, B, and C, representing three phases, operating with a 120-degree electrical offset. Thus, the phases run along a common axis. As shown, each phase assembly 50 includes a first flux loop 142A and a second flux loop 142B. The spikes of each flux pair of the first flux loop 142A and the second flux loop 142B are respectively positive and negative poles of opposite polarity, shown as "+" and "-". Each pole of flux loops 142A and 142B is simultaneously positively or negatively polarized 360 degrees around the common axis CA. The opposite polarization direction between the first flux loop 142A and the second flux loop 142B of each phase assembly 50 varies with the sinusoidal input signal of the corresponding coil of the phase assembly 50. Since the first flux ring 142A and the second flux ring 142B are axially aligned and loaded in opposite directions, an axial force can be generated between them and the magnet of the rotor, except that this axial force is balanced and canceled out by the two oppositely polarized first flux rings 142A and 142B. Each ring 142A, 142B is completely polarized around the common axis CA, thus balancing the load. Over time, wear may degrade the normal function of any motor, and this degradation may lead to an imbalance between the first flux ring 142A and the second flux ring 142B relative to the magnet (e.g., due to losses or defects in materials such as coils). This imbalance, due to the axially oriented phases, will only axially drive the motor 24 along the common axis, and thus drive the driver 26 and the fluid displacement member 34. This undesirable force will not cause problems because the pump 28 is configured to move the fluid displacement member 34 axially. Therefore, the motor 24 prevents undesirable lateral loads on the fluid displacement member 34.

[0142] Figure 11 A schematic diagram of a pump 28''' operated by a conventional radial flux electric motor 24'' is shown, where the coils are arranged around a common axis rather than along it. Therefore, phases A, B, and C are arranged around the common axis. Pump 28''' can be substantially similar to any of pumps 28, 28', and 28''. Not only are there fewer magnetic poles used to uniformly distribute the force around the common axis, but phase imbalances due to wear also generate torque on the rotor, as shown by the downward force illustrated. This relates to... Figure 10The imbalance that generates axial force, as discussed, forms a contrast. This erroneous force on motor 24" will cause motor 24" to rotate about drive 26', which can be substantially similar to drive 26', with any degree of play present in drive 26', thereby pushing fluid displacement member 34'' off the common axis and loading the sides of fluid displacement member 34''. This will cause fluid displacement member 34'' to wear prematurely, especially if fluid displacement member 34'' is relied upon to provide a dynamic sealing surface, for example, if it is a piston. The radial force D in motor 24'' can induce a radial reaction force E in pump 28'''. Therefore, the motor according to this disclosure has advantages over conventional radial flux motors in operating pumps and similar fluid moving equipment.

[0143] Figure 12A This is a schematic block diagram of a prior art pump device 200. Figure 12B This is a schematic end view of a conventional AC induction motor 202. As shown, the end turns 210 of the coil 212 extend closer to the fluid displacement member 34 than the steel laminate 214 and the magnet 216. These end turns 210 serve little purpose other than returning the loops of the coil 212 to overlap with the steel laminate 214. The absence of such end turns 210, as in motors 24, 24', reduces the length of the motor and eliminates the weight and cost associated with such end turns 210.

[0144] The prior art pump device 200 includes a driver 218 formed by a reduction gear 220, which increases torque and reduces the output speed of the motor 202. The reduction gear 220 connects the pump 222, and in particular the fluid displacement member 224, to the motor 202. The fluid displacement member 224 reciprocates on an axis that is not aligned with the axis of rotation of the rotor of the motor 202. In the example shown, the axis is transverse. The gear assembly 220 adds offset and additional structure, resulting in the misalignment of the axis of the fluid displacement member 224 with the axis of the motor 202.

[0145] While the pumping assemblies described in this disclosure and claims are set within the context of jet systems, it should be understood that the pumping assemblies and control devices can be used in a variety of fluid movement contexts and systems and are not limited to those described. Any one or more of the pumping assemblies described may be used alone or in conjunction with one or more additional pumps to move fluid for any desired purpose, such as location transfer, spraying, metering, application, propulsion, etc.

[0146] Although the invention has been described with reference to exemplary embodiments, those skilled in the art will understand that various changes can be made and elements can be substituted with equivalents without departing from the scope of the invention. Furthermore, many modifications can be made to adapt particular situations or materials to the teachings of the invention without departing from its essential scope. Therefore, the invention is intended to be limited to the specific embodiments disclosed, but rather to include all embodiments falling within the scope of the appended claims.

Claims

1. A pumping device for pumping fluid, the device comprising: An electric motor configured to produce a rotational output, the electric motor comprising: A rotor configured to rotate about a common axis, the rotor comprising a plurality of magnets, each magnet being elongated and extending parallel to the common axis, the plurality of magnets being arranged in a ring around the common axis; and A stator configured to be energized to generate a magnetic flux that rotates the rotor, the stator comprising: Multiple coils, arranged along a common axis, each coil being coaxial with the common axis; and Multiple circular spike arrays arranged along the common axis, each of the multiple circular spike arrays comprising: Multiple spikes are arranged in a circle coaxial with the common axis, and all spikes are configured to be simultaneously polarized by the coils of the multiple coils to generate a magnetic flux that causes the rotor to rotate relative to the stator. A driver configured to convert the rotary output from the electric motor into a linear reciprocating output; and A fluid displacement member, configured to receive a linear reciprocating output from the driver, to reciprocate linearly along the common axis to pump fluid. The plurality of coils are arranged along the common axis such that each coil does not overlap with any other coil in the plurality of coils in the radial direction.

2. A pumping device for moving liquid, the device comprising: An electric motor configured to produce a rotational output, the electric motor comprising: A rotor configured to rotate about a common axis, the rotor comprising a plurality of magnets, each magnet being elongated and extending parallel to the common axis, the plurality of magnets being arranged in a ring around the common axis; and A stator configured to be energized to generate a magnetic flux that rotates the rotor, the stator comprising: Multiple coils, arranged along a common axis, each coil being coaxial with the common axis; and Multiple circular spike arrays arranged along the common axis, each of the multiple circular spike arrays comprising: A plurality of spikes arranged in a circle coaxial with the common axis, all of the spikes being configured to be simultaneously polarized by coils of a plurality of coils to generate magnetic flux that rotates the rotor relative to the stator; and A fluid displacement member configured to rotate about the common axis via the rotor to move liquid; The stator includes a first phase component, which includes a first circular spike array of the plurality of circular spike arrays, a second circular spike array of the plurality of circular spike arrays, and a first coil of the plurality of coils arranged directly axially between the first circular spike array and the second circular spike array.

3. An apparatus for moving a liquid, the apparatus comprising: An electric motor configured to produce a rotational output, the electric motor comprising: A rotor configured to rotate about a common axis, the rotor comprising a plurality of magnets, each magnet being elongated and extending parallel to the common axis, the plurality of magnets being arranged in a ring around the common axis; and A stator configured to be energized to generate a magnetic flux that rotates the rotor, the stator comprising: A plurality of phase components, the plurality of phase components being arranged along the common axis, each of the plurality of phase components comprising: A coil, the coil extending about the common axis and configured to be coaxial with the common axis; and A first circular spike array, comprising a first plurality of spikes arranged in a circle coaxial with the common axis; The second circular spike array includes a second plurality of spikes arranged in a circle coaxial with the common axis; Wherein, all the protrusions of the first plurality of protrusions and all the protrusions of the second plurality of protrusions are configured to be simultaneously polarized by the coils arranged directly axially between the first and second circular protrusion arrays to generate magnetic flux that causes the rotor to rotate relative to the stator; and A fluid displacement member configured to be moved by the output of the electric motor, wherein at least one spike of the plurality of phase components of the stator is arranged to be closer to the fluid displacement member than any coil of the plurality of phase components.

4. A pumping device for moving liquid, the pumping device comprising: An electric motor configured to generate a rotational output, the electric motor including a first motor end and a second motor end, the first motor end being oriented along a rotation axis in a first axial direction, and the second motor end being oriented along the rotation axis in a second axial direction, the electric motor comprising: A rotor configured to rotate about the axis of rotation, the rotor comprising an array of permanent magnets arranged in a ring around the axis of rotation; and A stator configured to be energized to generate a magnetic flux that rotates the rotor, the stator comprising: Multiple coils, the multiple coils being arranged along the axis of rotation; and Multiple circular spike arrays are arranged along the rotation axis, and each of the multiple circular spike arrays comprises: Multiple spikes arranged in a circle coaxial with the axis of rotation, wherein each of the multiple spikes is configured to be simultaneously polarized by a coil of the multiple coils to generate a magnetic flux that causes the rotor to rotate relative to the stator. A driver connected to the rotor, the driver being axially spaced outward from the rotor such that the end of the driver closest to the motor is spaced from the rotor in the first axial direction along the axis of rotation; the driver is configured to receive a rotational output from the rotor and convert the rotational output into linear motion; and A pump comprising a pump body and a fluid displacement element configured to be driven by a driver to reciprocate within the pump body along a pump axis to pump fluid, wherein each coil of a plurality of coils lacks an end turn extending axially beyond any of the plurality of protrusions, the coils of the plurality of coils being disposed between the plurality of protrusions such that at least one protrusion of the plurality of circular protrusions is positioned closer to the fluid displacement element than a coil of the plurality of coils disposed between the plurality of circular protrusions; and A frame that keeps both the stator and the pump body stationary, while the rotor moves the fluid displacement element via the driver, wherein the frame extends radially wider than both the plurality of circular spike arrays and the rotor; The first motor end is oriented toward the pump, the second motor end is oriented away from the pump, the stator is mounted on a shaft, and the shaft is connected to the frame on the axial side of the electric motor opposite to the pump.

5. A pumping device for pumping fluid, the device comprising: An electric motor configured to produce a rotational output, the electric motor comprising: A motor rotor configured to rotate about a common axis, the motor rotor including an array of permanent magnets arranged in a ring around the common axis; and A motor stator configured to be energized to generate a magnetic flux that rotates the motor rotor, the motor stator comprising: A plurality of coils, arranged along the common axis, each coil of the plurality of coils being coaxial with the common axis; and Multiple circular spike arrays, arranged in pairs along the common axis, Each of the plurality of circular spike arrays comprises: Multiple spikes are arranged in a circle coaxial with the common axis, wherein all spikes in the respective circular spike array are configured to be simultaneously polarized by a corresponding coil of the plurality of coils to generate a magnetic flux that causes the motor rotor to rotate relative to the motor stator. Each set of paired circular spike arrays includes a first circular spike array and a second circular spike array, and each corresponding coil of the plurality of coils is located between a corresponding set of paired circular spike arrays; and Each set of the paired circular spike arrays includes a plurality of axial return sections, the axial return sections extending such that each of the plurality of axial return sections radially overlaps with a first circular spike array and a second circular spike array of the set of the paired circular spike arrays to allow magnetic flux loops polarized by multiple pairs of spikes on the first and second circular spike arrays; and A fluid pump operably connected to the electric motor for being powered by the electric motor, the fluid pump comprising: Pump stator; and A pump rotor, coaxial with and connected to the electric motor along the common axis to receive rotational output from the motor rotor, is configured to rotate relative to the pump stator on the pump axis coaxial with the common axis to pump fluid. The fluid pump includes an elastomer that forms a series of leaf cavities to allow for the gradual movement of multiple corresponding cavities along the common axis.

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