Pump and fluid shifter for pump

Abstract

An electrically operated displacement pump includes an electric motor having a stator and a rotor. The rotor is connected to the fluid shifter to drive the fluid shifter for axial reciprocating motion. A controller controls operation of the motor based on an operating state of the motor to control pumping of the displacement pump. The controller is configured to operate the pump in a startup mode during startup of the pump, and to operate the pump in a pumping mode during pumping of process fluid. The controller causes the fluid shifter to move differently in the activation mode than in the pumping mode.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims the benefit of U.S. Provisional Application No. 63 / 359,515, filed on July 8, 2022, entitled “PUMP,” the disclosure of which is incorporated herein by reference in its entirety. Background Art

[0002] The present disclosure relates to positive displacement pumps. More particularly, the present disclosure relates to control systems for positive displacement pumps. The present disclosure also relates to diaphragms for positive displacement pumps.

[0003] Positive displacement pumps discharge a process fluid based on a selected discharge parameter, such as flow or pressure. In a typical positive displacement pump, a fluid displacing member, typically a piston or diaphragm, pumps the process fluid.

[0004] Fluid-operated double displacement pumps typically employ a diaphragm as a fluid displacement member and use air or hydraulic fluid as a working fluid to drive the fluid displacement member. In an air-operated double displacement pump, two diaphragms are connected by an axis and compressed air is the working fluid. Compressed air is applied to one of the two chambers associated with the corresponding diaphragm. The compressed air applies force to all portions of the diaphragm that are exposed to the air chamber containing the compressed air. When compressed air is supplied to the first chamber, the first diaphragm is driven through the pumping stroke and pulls the second diaphragm through the suction stroke. When compressed air is supplied to the second chamber, the diaphragm moves through the reverse stroke. The delivery of compressed air is controlled by an air valve, and the air valve is usually mechanically actuated by a diaphragm. One diaphragm is pulled until the diaphragm causes the actuator to toggle the air valve. Toggling the air valve discharges compressed air from the first chamber to the atmosphere and introduces fresh compressed air into the second chamber, causing the corresponding diaphragm to reciprocate.

[0005] The double displacement pump can also be mechanically operated so that the pump does not require the use of a working fluid. In this case, a motor is operatively connected to the fluid displacement member to drive the reciprocating motion. A gear train is arranged between the motor and the shaft connected to the fluid displacement member to ensure that the pump can provide sufficient torque during pumping. The motor and gear train are arranged outside the body of the pump. Summary of the invention

[0006] According to one aspect of the present disclosure, a pump for pumping a fluid comprises: a first fluid chamber; a first inlet check valve and a first outlet check valve, the first inlet check valve and the first outlet check valve being positioned upstream and downstream of the first fluid chamber, respectively, and regulating flow into and out of the first fluid chamber; an electric motor, the electric motor comprising a stator and a rotor, the rotor being configured to generate a rotational output; a driver, the driver converting the rotational output from the electric motor into a linear reciprocating motion; a first fluid displacer, the first fluid displacer being configured to be driven by the driver at least partially to perform a linear reciprocating motion within the first fluid chamber to pump the fluid, wherein the first fluid displacer reciprocates through a series of continuous pump cycles, each pump cycle including a pumping stroke phase, a suction stroke phase and a conversion phase, wherein the conversion phase occurs at each transition between the pumping stroke phase and the suction stroke phase, and during the conversion phase, the first fluid displacer reverses direction; and a controller configured to regulate energy delivery to the electric motor in a starting mode in which the pump is activated and in a pumping mode, and wherein the controller regulates the energy delivery in the starting mode so that the rotor rotates to cause the first fluid displacer to move differently in the starting mode than in the pumping mode.

[0007] According to additional or alternative aspects of the present disclosure, a pump for pumping fluid comprises: a first fluid chamber; a first inlet check valve and a first outlet check valve, wherein the first inlet check valve and the first outlet check valve are respectively positioned upstream and downstream of the first fluid chamber and regulate flow into and out of the first fluid chamber; an electric motor, wherein the electric motor comprises a stator and a rotor, wherein the rotor is configured to generate a rotational output; a driver, wherein the driver converts the rotational output from the electric motor into a linear reciprocating motion; a first fluid displacer, wherein the first fluid displacer is configured to be driven by the driver at least partially to perform a linear reciprocating motion within the first fluid chamber to pump the fluid, wherein the first fluid The shifter reciprocates through a series of continuous pump cycles, each pump cycle including a pumping stroke phase, a suction stroke phase and a conversion phase, wherein the conversion phase occurs at each transition between the pumping stroke phase and the suction stroke phase, and during the conversion phase, the first fluid shifter reverses direction; and a controller, the controller being configured to regulate energy delivery to the electric motor in a starting mode in which the pump is activated and in a pumping mode, wherein the controller regulates the energy delivery based on a target starting speed of the first fluid shifter in the starting mode and based on a target pumping speed of the first fluid shifter in the pumping mode, the target starting speed being greater than the target pumping speed.

[0008] According to another additional or alternative aspect of the present disclosure, a pump for pumping fluid comprises: a first fluid chamber; a first inlet check valve and a first outlet check valve, wherein the first inlet check valve and the first outlet check valve are respectively positioned upstream and downstream of the first fluid chamber and regulate the flow into and out of the first fluid chamber; an electric motor, wherein the electric motor comprises a stator and a rotor, wherein the rotor is configured to generate a rotational output; a driver, wherein the driver converts the rotational output from the electric motor into a linear reciprocating motion; and a first fluid displacer, wherein the first fluid displacer is configured to be driven by the driver to perform a linear reciprocating motion along an axis and at least partially within the first fluid chamber to pump the fluid. body, wherein the first fluid displacer reciprocates through a series of consecutive pump cycles, each pump cycle comprising: a first stroke along the axis in a first direction, a second stroke along the axis in a second direction, a first transition of the first fluid displacer from reversing direction from the first stroke to the second stroke, and a second transition of the first fluid displacer from reversing direction from the second stroke to the first stroke; and a controller, the controller being configured to regulate energy delivery to the electric motor in a starting mode in which the pump is activated and in a pumping mode, wherein the controller regulates the energy delivery so that the first fluid displacer moves differently in the starting mode than in the pumping mode.

[0009] According to another additional or alternative aspect of the present disclosure, a pump for pumping fluid, the pump comprising: a first fluid chamber; a first inlet check valve and a first outlet check valve, the first inlet check valve and the first outlet check valve being positioned upstream and downstream of the first fluid chamber, respectively, and regulating flow into and out of the first fluid chamber; an electric motor, the electric motor comprising a stator and a rotor, the rotor being configured to generate a rotational output; a driver, the driver converting the rotational output from the electric motor into a linear reciprocating motion; a first fluid displacer, the first fluid displacer being configured to be driven by the driver to perform a linear reciprocating motion along an axis and at least partially within the first fluid chamber to pump the fluid, wherein the first fluid displacer is driven by a series of continuous The pump cycle performs reciprocating motion, each pump cycle including: a first stroke along the axis in a first direction, a second stroke along the axis in a second direction, a first conversion of the first fluid displacer from the first stroke to the second stroke, and a second conversion of the first fluid displacer from the second stroke to the first stroke; and a controller, the controller being configured to regulate energy delivery to the electric motor in a starting mode in which the pump is started and in a pumping mode, wherein the controller regulates the energy delivery so that the first fluid displacer moves a first distance through the first stroke in the starting mode, and the fluid displacer moves a second distance through the first stroke in the pumping mode, the first distance being greater than the second distance.

[0010] According to yet another additional or alternative aspect of the present disclosure, a pump for pumping a fluid comprises: a first fluid chamber; a first inlet check valve and a first outlet check valve, wherein the first inlet check valve and the first outlet check valve are respectively positioned upstream and downstream of the first fluid chamber and regulate flow into and out of the first fluid chamber; an electric motor, wherein the electric motor comprises a stator and a rotor, wherein the rotor is configured to generate a rotational output; a driver, wherein the driver converts the rotational output from the electric motor into a linear reciprocating motion; and a first fluid displacer, wherein the first fluid displacer is configured to be driven by the driver at least partially to perform a linear reciprocating motion within the first fluid chamber to pump the fluid, wherein , the first fluid displacer reciprocates through a series of consecutive pump cycles, each pump cycle including a pumping stroke phase, a suction stroke phase and a conversion phase, the conversion phase occurring at each transition between the pumping stroke phase and the suction stroke phase, during which the first fluid displacer reverses direction; and a controller, the controller being configured to regulate energy delivery to the electric motor in a starting mode in which the pump is activated and in a pumping mode, and wherein the controller regulates the energy delivery in the starting mode so that the rotor rotates to cause the first fluid displacer to cause the conversion phase during the starting mode to be slower than the conversion phase during the pumping mode.

[0011] According to yet another additional or alternative aspect of the present disclosure, a pump for pumping a fluid comprises: a first fluid chamber; a first inlet check valve and a first outlet check valve, wherein the first inlet check valve and the first outlet check valve are respectively positioned upstream and downstream of the first fluid chamber and regulate flows into and out of the first fluid chamber; an electric motor, wherein the electric motor comprises a stator and a rotor, wherein the rotor is configured to generate a rotational output; a driver, wherein the driver converts the rotational output from the electric motor into a linear reciprocating motion; a first fluid displacer, wherein the first fluid displacer is configured to be driven by the driver at least partially to perform a linear reciprocating motion within the first fluid chamber to pump the fluid, wherein the first fluid displacer is driven by a series of Continuous pump cycles perform reciprocating motion, each pump cycle includes a pumping stroke phase, a suction stroke phase and a conversion phase, wherein the conversion phase occurs at each transition between the pumping stroke phase and the suction stroke phase, and during the conversion phase, the first fluid displacer reverses direction; and a controller, the controller being configured to regulate energy delivery to the electric motor in a starting mode in which the pump is activated and in a pumping mode, and wherein the controller regulates the energy delivery in the starting mode so that the first fluid displacer pauses for a first time period during the conversion phase during the starting mode and pauses for a second time period during the conversion phase in the pumping mode, the first time period being longer than the second time period.

[0012] According to yet another additional or alternative aspect of the present disclosure, a pump for pumping fluid comprises: a first fluid chamber; a first inlet check valve and a first outlet check valve, wherein the first inlet check valve and the first outlet check valve are respectively positioned upstream and downstream of the first fluid chamber and regulate flow into and out of the first fluid chamber; an electric motor, wherein the electric motor comprises a stator and a rotor, wherein the rotor is configured to generate a rotational output; a driver, wherein the driver converts the rotational output from the electric motor into a linear reciprocating motion; and a first fluid displacer, wherein the first fluid displacer is configured to be driven by the driver at least partially to perform a linear reciprocating motion within the first fluid chamber to pump the fluid, wherein the The first fluid displacer reciprocates through a series of continuous pump cycles, each pump cycle including a pumping stroke phase, a suction stroke phase and a conversion phase, wherein the conversion phase occurs at each transition between the pumping stroke phase and the suction stroke phase, and during the conversion phase, the first fluid displacer reverses direction; and a controller configured to regulate energy delivery to the electric motor in a starting mode in which the pump is activated and in a pumping mode, and wherein the controller regulates the energy delivery in the starting mode so that the rotor rotates to cause the first fluid displacer to move differently through the conversion phase in the starting mode than through the conversion phase in the pumping mode.

[0013] According to yet another additional or alternative aspect of the present disclosure, a pump for pumping fluid comprises: a first fluid chamber; a first inlet check valve and a first outlet check valve, wherein the first inlet check valve and the first outlet check valve are respectively positioned upstream and downstream of the first fluid chamber and regulate flow into and out of the first fluid chamber; an electric motor, wherein the electric motor comprises a stator and a rotor, wherein the rotor is configured to generate a rotational output; a driver, wherein the driver converts the rotational output from the electric motor into a linear reciprocating motion; a first fluid displacer, wherein the first fluid displacer is configured to be driven by the driver to perform a linear reciprocating motion along an axis and at least partially within the first fluid chamber to pump the fluid, wherein the The first fluid displacer reciprocates through a series of continuous pump cycles, each pump cycle including: a first stroke along the axis in a first direction, a second stroke along the axis in a second direction, a first conversion of the first fluid displacer from the first stroke to the second stroke, and a second conversion of the first fluid displacer from the second stroke to the first stroke; and a controller, the controller is configured to regulate energy delivery to the electric motor in a starting mode in which the pump is activated and in a pumping mode, wherein the controller regulates the energy delivery so that the first fluid displacer moves through a conversion phase differently in the starting mode than in the pumping mode.

[0014] According to another additional or alternative aspect of the present disclosure, a diaphragm for a pump configured to reciprocate along an axis to pump a fluid comprises: a first diaphragm plate; and a flexible body extending radially outward from the diaphragm plate, the flexible body having an outer side and an inner side, the outer side being oriented in a first direction along the axis and being configured to be oriented toward a pumping chamber through which the fluid is pumped, and the inner side being oriented in a second direction along the axis and being configured to be oriented toward a motor that drives the reciprocating motion of the diaphragm. The flexible body comprises: a main diaphragm, the main diaphragm comprising a flange enlarged relative to the diaphragm body of the main diaphragm, the flange being configured to be clamped to mount the diaphragm to the pump; and a backing formed separately from the main diaphragm and arranged so that the main diaphragm is located between the backing and the outer side of the flexible body, the backing comprising a flange cup, the flange cup being open in the first direction and being configured to receive the flange.

[0015] According to another additional or alternative aspect of the present disclosure, a pump for pumping fluid includes: a pump body, the pump body at least partially defining a motor housing; an electric motor, the electric motor is arranged in the motor housing and is configured to generate a rotational output; a driver, the driver converts the rotational output from the electric motor into a linear reciprocating motion along an axis; a first fluid chamber, the first fluid chamber is at least partially defined by a first fluid cover connected to the pump body; and a first diaphragm, the first diaphragm is configured to be driven by the driver at least partially in the first fluid chamber along the axis Linear reciprocating motion to pump the fluid through the first fluid chamber. The first diaphragm includes: a first diaphragm plate and a flexible body, the flexible body extending radially outward from the diaphragm plate and at least partially defining the first fluid chamber, the flexible body having an outer side oriented toward the first fluid chamber and an inner side oriented toward the electric motor. The flexible body includes: a main diaphragm, the main diaphragm including a flange enlarged relative to the diaphragm body of the main diaphragm; and a backing, the backing is formed separately from the main diaphragm and arranged so that the backing is located between the main diaphragm and the electric motor, the backing including a flange cup configured to receive the flange, the flange cup axially open away from the electric motor. The flange is clamped between the first fluid cover and the pump body together with the flange cup. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1A It is a front isometric view of an electrically operated pump.

[0017] Figure 1B is a rear isometric view of an electrically operated pump.

[0018] Figure 1C is a schematic block diagram of an electrically operated pump.

[0019] Figure 2A is along Figure 1B A cross-sectional view taken along line AA in FIG.

[0020] Figure 2B yes Figure 2A Magnified view of detail B.

[0021] Figure 2C is along Figure 1A Cross-sectional view taken along line CC in FIG.

[0022] Figure 2D is along Figure 2C A cross-sectional view taken along line DD in FIG.

[0023] Figure 3 is an isometric partial cutaway view showing the motor and drive of an electrically operated pump.

[0024] Figure 4 is an isometric view of the driver with a portion of the drive nut removed.

[0025] Figure 5 is an isometric view of the driver with a portion of the drive nut removed.

[0026] Figure 6 yes Figure 5 An isometric view of the driver is shown with the body of the drive nut removed to show the rolling elements.

[0027] Figure 7 is a block diagram of an electrically operated pump.

[0028] Figure 8 is a schematic diagram illustrating the switching position of a fluid displacer of a pump.

[0029] Fig. 9A is a cross-sectional view of the pump.

[0030] Fig. 9B yes Fig. 9A Magnified view of detail B.

[0031] Fig. 9C is a cross-sectional view showing the fluid displacer disassembled from the pump and in a partially unassembled state.

[0032] Fig.10 is a cross-sectional view showing the fluid displacer assembled to the driver and disassembled from the pump. DETAILED DESCRIPTION

[0033] According to aspects of the present disclosure, the pump is configured to operate in a startup mode and a pumping mode. The controller regulates the energy delivery to the electric motor, which drives the displacement of one or more fluid shifters of the pump. The controller can cause the pump to operate in the startup mode to start the pump, and can cause the pump to operate in the pumping mode to pump the process fluid. The controller can be configured so that the fluid shifter has different drive profiles during the startup mode and the pumping mode. The controller can cause the fluid shifter to move differently when the pump is operated in the startup mode and when the pump is operated in the pumping mode.

[0034] According to some aspects of the present disclosure, the controller can cause the pump to operate so that the velocity profile, acceleration profile, deceleration profile, displacement distance profile, and / or one or more other movement profiles of the fluid displacer change between a startup mode and a pumping mode. The controller can be configured to cause the fluid displacer to move through a stroke during startup at a different speed than through a stroke during pumping. Additionally or alternatively, the controller can be configured to cause the fluid displacer to travel a different distance in a stroke during startup than in a stroke during pumping. Additionally or alternatively, the controller can be configured to cause the fluid displacer to accelerate and / or decelerate at a different rate during startup than during pumping.

[0035] According to various aspects of the present disclosure, the controller can be configured to control the displacement of the fluid shifter so that the conversion profile of the fluid shifter in the startup mode is different from the conversion profile of the fluid shifter in the pumping mode. When the fluid shifter reverses direction to change the stroke direction between pump strokes, a conversion occurs. For example, when the fluid shifter reverses from moving in a first direction along the reciprocating axis to moving in the opposite second direction along the reciprocating axis, a conversion can be considered to occur. Based on the operating parameters of the pump or based on the portion of the length of the pump stroke and other options, a conversion can be considered to occur. In some examples, based on the start of deceleration until the fluid shifter begins to move in the opposite axial direction, a conversion can be considered to occur. In some examples, the fluid shifter can be considered to be in conversion when it is in the last 20%, 15%, 10% or 5% of the end of the pump stroke and other distance options. The controller can be configured to operate the pump so that the conversion takes a different amount of time during the startup mode than during the pumping mode.

[0036] The fluid displacer necessarily pauses for at least a short period of time during the transition, when the fluid displacer stops moving along the axis in a first direction and then begins moving along the axis in an opposite second direction. The controller may purposefully pause the fluid displacer during the transition in the start-up mode so that the fluid displacer remains stationary for a set period of time before beginning to move in the second direction. The controller may control the delivery of energy to the electric motor so that the fluid displacer is stationary for a longer period of time during the transition in the start-up mode than in the pumping mode.

[0037] The controller can be configured to determine an operating state of the pump and control the operation of the pump based on the determined operating state. The controller can receive parameter information about the operation of the pump, such as fluid parameters (e.g., pressure, flow, etc. of the process fluid output by the pump) and / or operating parameters (e.g., the current draw of the electric motor of the pump). The controller can determine whether the pump needs to be started based on the parameter information. The controller can cause the pump to operate in a starting mode based on the controller determining that the pump needs to be started.

[0038] The controller can be configured to automatically cause the pump to exit the startup mode and operate in the pumping mode. In some examples, the controller can cause the pump to exit the startup mode and enter the pumping mode based on a pumping threshold. For example, the pumping threshold can be based on parameter information. The controller can compare the parameter information to one or more thresholds to determine whether the pump has been activated and should be operated in the pumping mode. For example, the controller can determine that the pump has been activated based on the current draw of the electric motor.

[0039] Additionally or alternatively, the controller may cause the pump to exit the startup mode based on a count threshold, such that the controller switches the pump from the startup mode to the pumping mode based on a count reaching a threshold (e.g., a time count, a pumping stroke count, a transition count, a pump cycle count, etc.). The controller may also cause the pump to enter the startup mode based on a count threshold. The controller may cause the pump to operate in the pumping mode for a minimum period of time (e.g., a minimum time period, a minimum number of pump strokes, a minimum number of transitions, a minimum number of pump cycles, etc.) before entering the startup mode, either at system startup or after exiting the startup mode.

[0040] According to various aspects of the present disclosure, a diaphragm for a displacement pump includes a flexible body formed by a stacked main diaphragm and a backing. The main diaphragm and the backing are formed separately and stacked together to form the flexible body of the diaphragm. The main diaphragm includes a flange that is clamped for fixing the diaphragm relative to other components of the pump. The backing can be arranged adjacent to the main diaphragm and can cover an axial side of the main diaphragm. The backing is arranged on the dry side of the flexible body so that the backing is arranged on the axial side of the flexible body opposite to the side oriented toward the fluid chamber, and the process fluid is pumped through the fluid chamber by the fluid displacer. During pumping, the main diaphragm can be exposed to the process fluid in the fluid chamber. The backing is thinner than the main diaphragm. The backing is configured to provide reinforcement and support to the body. The backing is arranged axially between the driver and the main diaphragm of the pump. The backing enhances the stiffness of the diaphragm and reduces the wear of the diaphragm during pumping. The backing may be formed of a different material than the main diaphragm, or may be formed of the same material as the main diaphragm, depending on the configuration of the diaphragm.

[0041] Figure 1A is a front isometric view of an electrically operated pump 10 . Figure 1B is a rear isometric view of the pump 10 . Figure 1C is a schematic block diagram of the pump 10. Figures 1A to 1CThe pump 10 includes an inlet manifold 12, an outlet manifold 14, a pump body 16, fluid covers 18a, 18b (collectively referred to herein as "a fluid cover 18" or "multiple fluid covers 18"), fluid displacers 20a, 20b (collectively referred to herein as "a fluid displacer 20" or "multiple fluid displacers 20"), a motor 22, a driver 24, and a controller 26. The motor 22 includes a stator 28 and a rotor 30. Fluid chambers 34a, 34b (collectively referred to herein as "a fluid chamber 34" or "multiple fluid chambers "34") are shown.

[0042] The pump body 16 is disposed between the fluid covers 18a, 18b. The motor 22 is at least partially disposed within the pump body 16. The pump body 18 can be considered to at least partially define a motor housing, and the motor 22 is disposed within the motor housing. In the example shown, the motor 22 is coaxial with the fluid displacer 20, as discussed in more detail below. The axis of rotation of the rotor 30 of the motor 22 is coaxially arranged with the reciprocating axis of one or more of the fluid displacers 20. In the example shown, the axis of rotation is coaxial with the reciprocating axis of each of the two fluid displacers 20.

[0043] The motor 22 is an electric motor having a stator 28 and a rotor 30. The stator 28 includes an armature winding, and the rotor 30 includes a permanent magnet. The rotor 30 is configured to rotate about the pump axis PA in response to a current (such as a direct current (DC) signal and / or an alternating current (AC) signal) through the stator 28. The controller 26 is configured to regulate the electrical energy to the motor 22 to control the operation of the motor 22 and thereby control the displacement of the fluid displacer 20. The motor 22 is a reversible motor in which the stator 28 can cause the rotor 30 to rotate about the rotation axis of the rotor 30 in either of two rotational directions (e.g., alternating between clockwise and counterclockwise). The rotor 30 can rotate in a first rotational direction to displace the fluid displacer 20 in a first direction along the axis PA, and the rotor 30 can rotate in a second rotational direction opposite to the first rotational direction to displace the fluid displacer 20 in a second direction opposite to the first direction along the axis PA along the axis PA. The rotor 30 is connected to the fluid displacer 20 via a driver 24, which receives the rotational output from the rotor 30 and provides a linear reciprocating input to the fluid displacement member 20. The driver 24 is configured to convert the rotational output from the motor 22 into linear reciprocating motion. For example, the driver 24 can be a ball screw, a crank, a scotch yoke, and other options.

[0044] The fluid displacer 20 may be of any type suitable for pumping fluid from the inlet manifold 12 to the outlet manifold 14, such as a diaphragm or a piston. Although the pump 10 is shown as including two fluid displacers 20, it should be understood that some examples of the pump 10 include a single fluid displacer 20 or more than two fluid displacers 20. Furthermore, although the two fluid displacers 20 are shown herein as diaphragms, in various other embodiments, the two fluid displacers 20 may alternatively be pistons, and the teachings provided herein may be applied to piston pumps.

[0045] The controller 26 is electrically and / or communicatively connected to the motor 22 in an operable manner to control the operation of the motor 22. A user interface 27 of the controller 26 is shown. During operation, a power signal is provided to the stator 28 to cause the stator 28 to drive the rotor 30 to rotate. The driver 24 receives a rotational output from the rotor 30 and converts the rotational output into a linear output to linearly drive the fluid displacer 20 along a reciprocating axis of the fluid displacer 20, which may be coaxial with the pump axis PA. In some examples, the rotor 30 rotates in a first rotational direction to drive the fluid displacement member 20 along the axis in a first axial direction AD1, and the rotor 30 rotates in a second rotational direction to drive the fluid displacement member 20 along the axis in a second axial direction AD2. The pump 10 is shown to include a pump axis PA, which in the example shown is coaxial with the rotational axis of the rotor 30 and the reciprocating axis of the fluid displacer 20.

[0046] The driver 24 causes the fluid displacer 20 to reciprocate along the pump axis PA through alternating displacement strokes. The controller 26 is configured to regulate the delivery of energy to the electric motor 22 to cause the fluid displacer 20 to move through pump cycles. Each pump cycle includes: a first stroke along the pump axis PA in a first direction; a second stroke along the pump axis PA in a second direction; a first transition in which the fluid displacer 20 reverses direction from the first stroke to the second stroke; and a second transition in which the fluid displacer 20 reverses direction from the second stroke to the first stroke.

[0047] The displacement stroke may be a suction stroke and a pumping stroke. During the suction stroke of the fluid displacer 20, the volume of the fluid chamber 34 of the fluid displacer 20 is enlarged due to the movement of the fluid displacer 20, and during the pumping stroke, the volume of the fluid chamber 34 of the fluid displacer 20 is reduced due to the movement of the fluid displacer 20. Each of the suction stroke and the pumping stroke may be referred to as a displacement stroke. Each pump cycle includes two displacement strokes, one of which is a suction stroke and the other is a pumping stroke. During the suction stroke, the fluid displacement member 20 draws the process fluid from the inlet manifold 12 into the process fluid chamber 34, which is at least partially defined by the fluid cover 18 and the fluid displacer 20. During the pumping stroke, the fluid displacer 20 drives the process fluid from the fluid chamber 34 to the outlet manifold 14. Fluid flows from inlet manifold 12 to process fluid plenum 34 , and then from process fluid plenum 34 to outlet manifold 14 , as shown by fluid flow line FF.

[0048] Typically, depending on the arrangement of the check valve 56, the two fluid displacers 20 operate 180 degrees out of phase, so that the first fluid displacer 20 is driven by the pumping stroke (e.g., driving the process fluid from the pump 10 downstream) while the second fluid displacer 20 is driven by the suction stroke (e.g., pulling the process fluid from the upstream and into the pump 10). The two fluid displacers 20 also switch simultaneously (e.g., transition between the pumping stroke and the suction stroke), but have a phase difference of 180 degrees relative to each other. Although the example shown includes dual fluid displacers 20, it should be understood that the present disclosure is not limited to this. For example, the pump 10 can be configured to include a single fluid displacer 20, or more than two fluid displacers 20, such as three, four or more fluid displacers 20.

[0049] The driver 24 may also be referred to as a drive mechanism, the driver 24 is directly connected to the rotor 30, and the fluid displacer 20 is directly driven by the driver 24. Therefore, the motor 22 drives the fluid displacer 20 without an intermediate transmission device (e.g., a reduction transmission device). The wire 32 extends from the pump 10 and is configured to provide power to the electric components of the pump 10. The wire 32 can be connected to a wall outlet to provide power to the pump 10.

[0050] The fluid displacer 20a is arranged between the process fluid chamber 34a and the motor 12, and fluidically isolates the process fluid chamber 34a from the motor 12. The fluid displacer 20a moves along a first axial direction AD1 to reduce the volume of the process fluid chamber 34a, thereby driving the process fluid out of the process fluid chamber 34a. The fluid displacer 20a moves along a second axial direction AD2 opposite to the first axial direction AD1 to increase the volume of the process fluid chamber 34a, thereby drawing the process fluid from the inlet manifold 12 into the process fluid chamber 34a. The fluid displacer 20b is substantially similar to the fluid displacer 20a. The fluid displacer 20b pumps the process fluid through the process fluid chamber 34b. The fluid displacer 20b is connected to the fluid displacer 20a so that the displacement stroke is opposite between the two fluid displacers 20a and 20b. Thus, when fluid displacer 20b is driven in the second axial direction AD2, it moves through a pumping stroke of process fluid chamber 34b, and when fluid displacer 20b is driven in the first axial direction AD1, it moves through a suction stroke of process fluid chamber 34b.

[0051] During operation, fluid displacer 20 moves axially through a first displacement stroke and a second displacement stroke. During the first stroke, fluid displacer 20a moves through a pumping stroke for process fluid chamber 34a, and fluid displacer 20b moves through a suction stroke for process fluid chamber 34b. Fluid displacer 20 switches at the end of the first stroke and is driven in the opposite axial direction during a second stroke, during which fluid displacer 20a moves through a suction stroke for process fluid chamber 34a, and fluid displacer 20b moves through a pumping stroke for process fluid chamber 34b.

[0052] After completing the second stroke, the fluid displacer 20 is driven back through the first stroke and continues to pump the process fluid. In some examples, the fluid displacers 20a, 20b are arranged in parallel for pumping the process fluid. In this example, each fluid displacer 20 is located downstream of the inlet manifold 12 and upstream of the outlet manifold 14. None of the fluid displacers 20 is located upstream or downstream of another fluid displacer. None of the fluid displacers 20 receives process fluid from another fluid displacer 20 or provides process fluid to another fluid displacer 20.

[0053] Figure 2A is along Figure 1B A cross-sectional view of the pump 10 is taken along line AA in FIG. Figure 2B yes Figure 2A An enlarged view of a portion of the cross section shown in . Figure 2C is along Figure 1A 0 is a cross-sectional view of the pump 10 taken along line CC in FIG. Figure 2D is along Figure 2C The cross-sectional view taken along line DD in will be discussed together. FIG. 2A to FIG. 2D Pump body 16, fluid covers 18a, 18b, fluid displacers 20a, 20b, motor 22, driver 24, process fluid chambers 34a, 34b, bearings 54a, 54b, and motor nut 56 of pump 10 are shown.

[0054] The pump body 16 includes a central portion 66 and end caps 68a, 68b (collectively referred to herein as "an end cap 68" or "a plurality of end caps 68"). The central portion 66 includes a motor housing 70, a control housing 72, and a heat sink 74. The fluid displacers 20a, 20b include: inner plates 78a, 78b (collectively referred to herein as "an inner plate 78" or "a plurality of inner plates 78"); outer plates 80a, 80b (collectively referred to herein as "an outer plate 80" or "a plurality of outer plates 80"); flexible bodies 82a, 82b (collectively referred to herein as "a flexible body 82" or "a plurality of flexible bodies 82") and fasteners 84a, 84b.

[0055] The motor 22 includes a stator 28 and a rotor 30. The rotor 30 includes a permanent magnet array 86 and a rotor body 88. The motor 22 is disposed within the motor housing 70 between the end caps 68. The control housing 72 is connected to the motor housing 70 and extends from the motor housing 70. The control housing 72 is configured to house control elements of the pump 10, such as the controller 26 ( Figure 1C and Figure 7 ).

[0056] The driver 24 includes a drive nut 90, a lead screw 92, and rolling elements 98. The drive nut 90 includes a nut thread 102. The lead screw 92 includes a first lead screw end 104, a second lead screw end 106, a lead screw body 108, and a lead screw thread 110. The bearings 54a, 54b include inner raceways 122a, 122b, rollers 123a, 123b, and outer raceways 124a, 124b, respectively.

[0057] Components may be considered to overlap axially with one another when the components are arranged at a common radial position relative to an axis such that an axial line parallel to the axis extends through each of those axially overlapping components. Similarly, components may be considered to overlap radially when the components are arranged at a common axial position such that a radial line extending from the axis passes through each of those radially overlapping components.

[0058] End caps 68a, 68b are disposed on opposite lateral sides of the central portion 66 and attached to the central portion 66 to form the pump body 16. The housing fasteners 64 extend through the end caps 68 into the pump body 16 to secure the end caps 68 to the pump body 16. Although the end caps 68a, 68b are described as being removably mounted to the central portion 66, it should be understood that not all examples are so limited. In some examples, the pump body 16 may be integrally formed.

[0059] The heat sink 74 is formed on the central portion 66. The motor 22 is disposed within the motor housing 70 between the end caps 68. The end caps 68 may also be referred to as end walls. Although the end caps 68 are shown as being formed separately from and connected to the central portion 66, it should be understood that not all examples are so limited. For example, one or more of the end caps 68 may be integrally formed with the central portion 66.

[0060] The fluid covers 18a, 18b are connected to the pump body 16. In the example shown, the fluid covers 18a, 18b are mounted to the end caps 68a, 68b, respectively. The housing fasteners 64 secure the fluid covers 18 to the end caps 68. The inlet manifold 12 is connected to each fluid cover 18. The inlet pump check valves ( Figure 1C ) is arranged between the inlet manifold 12 and the fluid covers 18a, 18b. The inlet pump check valve in the pump check valve 58 is a one-way valve that is configured to allow flow into the process fluid chambers 34a, 34b and prevent reverse flow from the process fluid chambers 34a, 34b to the inlet manifold 12. The outlet manifold 14 is connected to each fluid cover 18. The outlet pump check valve ( Figure 1C ) is arranged between the outlet manifold 14 and the fluid covers 18a, 18b. The outlet pump check valve in the pump check valve 58 is a one-way valve that is configured to allow flow from the process fluid chambers 34a, 34b to flow out of the outlet manifold 14 and prevent reverse flow from the outlet manifold 14 to the process fluid chambers 34a, 34b. The pump check valve 58 can be configured as a ball valve, wherein the ball engages with the seat to close the valve, and the ball disengages from the seat to open the valve. In some examples, the pump check valve 58 does not include a biasing element that biases the valve toward a closed state, such as a spring connected to the ball. In some examples, the pump check valve 58 can be configured so that the valve member (e.g., a ball) is seated due to gravity and / or pressure changes in the associated fluid chamber 34 without the assistance of a biasing element.

[0061] The control housing 72 is connected to the motor housing 70 and extends from the motor housing 70. The control housing 72 is configured to house control elements of the pump 10, such as the controller 26 ( Figure 1C and Figure 7). The stator 28 surrounds the rotor 30 and drives the rotation of the rotor 30. In the example shown, the rotor 30 rotates about the pump axis PA and is arranged coaxially with the drive mechanism 24 and the fluid displacement member 20. The permanent magnet array 86 is arranged on the rotor body 88. The rotor 30 is arranged radially within the stator 28, so that the motor 22 is an inner rotary motor, but it should be understood that not all examples are limited to this. For example, the motor 22 can be configured as an outer rotary motor, in which the stator 28 is arranged within the rotor 30, so that the rotor 30 rotates around the stator 28.

[0062] The driver 24 receives the rotational output from the rotor 30 and converts the rotational output into a linear input to the fluid displacer 20. The motor 22 drives the reciprocating motion of the fluid displacer 20 through the driver 24 without any intermediate transmission device. The drive nut 90 is connected to the rotor body 88 to rotate with the rotor 30. The lead screw 92 is elongated along the pump axis PA and extends coaxially with the rotor 30 through the drive nut 90. In some examples, the permanent magnets in the permanent magnet array 86 can be mounted to the drive nut 90 so that the drive nut 90 forms the rotor body 88. In some examples, the rotor body 88 and the drive nut 90 can be integrally formed as a single block.

[0063] The rolling elements 98 are arranged between the rotor 30 and the lead screw 92. More specifically, the rolling elements 98 are arranged between the drive nut 90 and the lead screw 92. The rolling elements 98 are arranged in a raceway formed by the opposing nut threads 102 and the lead screw threads 110. The rolling elements 98 engage with the lead screw threads 110 to drive the linear displacement of the lead screw 92 along the pump axis PA. The rolling elements 98 can be balls or rollers, among other options, and as discussed in more detail below. The rolling elements 98 are arranged circumferentially around the lead screw 92 and are evenly arranged around the lead screw 92. The rolling elements 98 are arranged around an axis coaxial with the axis PA and are arranged along the axis. The rolling elements 98 separate the drive nut 90 from the lead screw 92 so that the drive nut does not directly contact the lead screw 92. Instead, both the drive nut 90 and the lead screw 92 ride on the rolling elements 98. The rolling elements 98 maintain a gap 99 ( Figure 3 ) to prevent contact between the drive nut 90 and the screw 92.

[0064] Bearings 54a, 54b are arranged at opposite axial ends of the rotor 30. The bearings 54 are configured to support both axial forces and radial forces. In some examples, the bearings 54 are tapered roller bearings, but it should be understood that other examples are possible. The bearing 54a is arranged at a first end of the rotor 30 around the drive nut 90. The bearing 54b is arranged at a second axial end of the rotor 30 around the drive nut 90.

[0065] The motor nut 56 is connected to the pump body 16. The motor nut 56 covers at least a portion of the axial end of the motor 22. In the example shown, the motor nut 56 is connected to the end cap 68a. The motor nut 56 and the end cap 68a can be connected by intersecting threads and other options. The motor nut 56 can compress the bearing 54 to preload the bearing 54.

[0066] The fluid displacer 20a, 20b is connected to the opposite ends 104, 106 of the lead screw 92, respectively. In the example shown, the fluid displacer 20 is flexible and includes a surface area that is variable during pumping. In the example shown, the fluid displacer 20 is formed as a diaphragm, including diaphragm plates 78, 80 and a flexible body 82. The flexible body 82 can be formed of a flexible material, such as rubber or other types of polymers. As discussed in more detail below, the flexible body 82 can be formed of multiple layers stacked axially. However, it should be understood that the fluid displacer 20 can be other configurations, such as a piston.

[0067] In the example shown, the fluid displacer 20a includes an inner plate 78a and an outer plate 80a arranged on opposite sides of a flexible body 82a. A portion of the flexible body 82a is captured between the opposing diaphragm plates 78a, 80a. The fluid displacer 20a is attached to the driver 24 at the first lead screw end 104 of the lead screw 92. A fastener 84a extends from the fluid displacement member 20a into the lead screw 92 to secure the fluid displacement member 20a to the lead screw 92. The fastener 84a extends through each outer plate 80a, the flexible body 82a and the inner plate 78a and enters the hole of the lead screw 92 to connect the fluid displacer 20a to the driver 24.

[0068] In the example shown, the fluid displacer 20b is similar to the fluid displacer 20a. A portion of the flexible body 82b is captured between the opposing diaphragm plates 78b, 80b. The outer plate 80b is overmolded by the flexible body 82b so that the outer plate 80b is at least partially arranged within the flexible body 82b. The flexible body 82b is overmolded on the outer plate 80b so that the outer plate 80b is not exposed to the process fluid. Fasteners 84b extend from the fluid displacer 20b and extend into the lead screw 92 to connect the fluid displacer 20b to the driver 24. Fasteners 84b extend from the outer plate 80b through the inner plate 78b and into the hole of the lead screw 92 to connect the fluid displacer 20b to the driver 24.

[0069] Although fluid displacers 20a, 20b are shown as different configurations, it should be understood that not all examples are so limited. For example, pump 10 can be configured such that each fluid displacer is configured similarly to fluid displacer 20a, or each fluid displacer is configured similarly to fluid displacer 20b.

[0070] The drive nut 90 and rolling elements 98 apply a rotational force to the lead screw 92 while axially driving the lead screw 92. As discussed above, the bearing 54 is configured to support both axial and radial forces. The lead screw 92 is connected to the fluid displacer 20 so that the fluid displacer 20 prevents the lead screw 92 from rotating about the pump axis PA. The fluid displacer 20 interfaces with the stationary components of the pump 10 (e.g., by being clamped between the fluid cover 18 and the pump body 16) to prevent the fluid displacer 20 and the lead screw 92 from rotating on the pump axis PA.

[0071] The outer edge 128a of the fluid displacer 20a is fixed between the fluid cover 18a and the pump body 16 to provide a liquid-tight seal between the wet side and the dry side of the fluid displacer 20a. The fluid cover 18a and the fluid displacer 20a at least partially define the process fluid chamber 34a. The outer edge 128a is clamped so that the fluid displacer 20a does not rotate on the pump axis PA. The outer edge 128a does not rotate around the pump axis PA. In the example shown, the outer edge 128a does not move axially relative to the pump axis PA during operation. The outer edge 128a includes a flange 136 seated in a mounting groove 138, which is formed by the opposite grooves of the fluid cover 18a and the pump body 16. The flange 136 has an increased thickness compared to the portion of the flexible body 82a adjacent to the flange 136.

[0072] The wet side of fluid displacer 20a is oriented toward fluid cover 18a and at least partially defines process fluid chamber 34a. In the example shown, a portion of outer plate 80a and fastener 84a are exposed to process fluid in process fluid chamber 34a. The dry side of fluid displacer 20a is oriented toward motor 22.

[0073] The outer edge 128b of the diaphragm 20b is fixed between the fluid cover 18b and the pump body 16 to provide a liquid-tight seal between the wet side and the dry side of the fluid displacement member 20b. The fluid cover 18b and the fluid displacer 20b at least partially define the process fluid chamber 34b. The outer edge 128b is clamped between the pump body 16 and the fluid cover 18b so that the outer edge 128b remains stationary and does not rotate around the pump axis PA. The outer edge 128b includes a flange 136 seated in a mounting groove 138, which is formed by relative grooves formed on the fluid cover 18b and the pump body 16. The flange 136 has an increased thickness compared to the portion of the flexible body 82b adjacent to the flange 136. The wet side of the fluid displacer 20b is oriented toward the end cap 68b and at least partially defines the process fluid chamber 34b. The dry side of the fluid displacer 20b is oriented toward the motor 22.

[0074] During operation, power is supplied to the stator 28 to drive the rotor 30 to rotate. The drive nut 90 is connected to the rotor body 88, and in some cases, forms or is integral with the rotor body 88, and rotates with the rotor 30. The rolling elements 98 drive the lead screw 92 linearly along the pump axis PA.

[0075] If initially along Figure 2A When the lead screw 92 is driven in the first axial direction AD1, the lead screw 92 pulls the fluid displacer 20b through the suction stroke and pushes the fluid displacer 20a through the pumping stroke. After reaching the end of the stroke in the first axial direction AD1, the rotor 30 is driven in the opposite rotational direction and the lead screw 92 is driven in the second axial direction AD2. When the lead screw 92 is driven in the direction AD2, the lead screw 92 pulls the fluid displacer 20a through the suction stroke and pushes the fluid displacer 20b through the pumping stroke. During the suction stroke, the volume of the process fluid chamber 34 increases, and the process fluid is drawn into the process fluid chamber 34 from the inlet manifold 12. During the pumping stroke, the volume of the process fluid chamber 34 decreases, and the fluid displacer 20 drives the process fluid out of the process fluid chamber 34 and flows downstream to the outlet manifold 14. The lead screw 92 drives the fluid displacer 20 through the corresponding pumping stroke and suction stroke. It should be understood that the size of the rotor 30 and the driver 24, 24', 24" can be set to provide any desired revolution to stroke ratio. For example, the pump 10 can have a revolution to stroke ratio of about 0.25:1 to about 7:1. In some examples, the pump 10 has a revolution to stroke ratio of about 0.5:1 to about 3:1. In a more particular example, the pump 10 has a revolution to stroke ratio of about 0.8:1 to about 1.5:1. A relatively large revolution to stroke ratio is conducive to a larger pumping pressure. A relatively small revolution to stroke ratio is conducive to a larger flow rate. In some examples, the size of the rotor 30 and the drive mechanism 24, 24', 24" is set so that one turn of the rotor 30 causes a complete stroke of the screw 92 in one of the first axial direction AD1 and the second axial direction AD2. The revolution to stroke ratio depends on the stroke length and lead (axial travel of a single turn) of the screw 92.

[0076] Figure 3 is an isometric partial cutaway view of the motor 22 and the drive 24. The motor 22 includes a stator 28 and a rotor 30, and is mounted in a motor housing 70. The rotor 30 includes a permanent magnet array 86 and a rotor body 88. The drive 24 includes a drive nut 90, a lead screw 92, and rolling elements 98. A gap 99 between the drive nut 90 and the lead screw 92 is shown.

[0077] The rotor 30 is arranged within the stator 28 along the pump axis PA. The drive nut 90 extends through the rotor 30 and is arranged coaxially with the rotor 30. The drive nut 90 is connected to the rotor body 88 so that the drive nut 90 rotates with the rotor 30 about the pump axis PA. Nut threads 102 are formed on the inner radial surface of the drive nut 90. The lead screw 92 extends axially through the drive nut 90 and is arranged coaxially with the rotor 30 and the drive nut 90. The lead screw threads 110 are formed on the outside of the lead screw body 108. Rolling elements 98 are arranged in a raceway formed by the lead screw threads 110 and the nut threads 102. The rolling elements 98 support the lead screw 92 relative to the drive nut 90 so that each of the drive nut 90 and the lead screw 92 rides on the rolling elements 98. The rolling elements 98 support the lead screw 92 relative to the drive nut 90 so that the drive nut 90 and the lead screw 92 do not contact during operation. The rolling elements 98 maintain a gap 99 between the drive nut 90 and the lead screw 92 and prevent contact therebetween.

[0078] The drive nut 90 rotates relative to the lead screw 92. The rolling elements 98 apply a force to the lead screw 92 at the lead screw threads 110 to cause axial displacement of the lead screw 92 along the pump axis PA. The rotor 30 can be driven in a first rotational direction, thereby driving the lead screw 92 in a first axial direction. The rotor 30 can be driven in a second rotational direction opposite to the first rotational direction, thereby driving the lead screw 92 in a second axial direction opposite to the first axial direction.

[0079] Figure 4 2 is a partial cross-sectional view of the driver 24 ′. The driver 24 ′ includes a drive nut 90 ′, a lead screw 92 , rolling elements 98 , and a ball return 140 .

[0080] The drive nut 90' surrounds a portion of the lead screw 92, and rolling elements 98 are arranged between the drive nut 90' and the lead screw 92. In the example shown, the rolling elements 98 are balls. Therefore, the drive mechanism 24' can be considered a ball screw. The rolling elements 98 support the drive nut 90' relative to the lead screw 92 so that the drive nut 90' does not contact the lead screw 92. The rolling elements 98 are arranged in a raceway formed by the lead screw threads 110 and the nut threads 102 (such as Figure 3 The ball return 140 is configured to pick up the rolling elements 98 and recirculate the rolling elements 98 within the raceway formed by the screw threads 110 and the nut threads 102. The ball return 140 can be of any type suitable for circulating the rolling elements 98. In some examples, the ball return 140 is an internal ball return such that the rolling elements 98 that are not within the raceway pass through the body of the drive nut 90'.

[0081] The drive nut 90' rotates relative to the lead screw 92 and causes the rolling elements 98 to apply an axial force to the lead screw 92 to drive the lead screw linearly. The driver 24' can thus convert a rotational input into a linear output.

[0082] Figure 5 is an isometric view of the drive mechanism 24 ″ with a portion of the drive nut 90 ″ removed. Figure 6 is an isometric view of the drive mechanism 24 ″ with the body of the drive nut 90 ″ removed to show the rolling elements 98 ′. Figure 5 and Figure 6 The driver 24 ″ includes a drive nut 90 ″, a lead screw 92 , and rolling elements 98 ′. The drive nut 90 ″ includes a drive ring 142 . Each of the rolling elements 98 ′ includes an end roller 144 and a roller shaft 146 .

[0083] The drive nut 90" surrounds a portion of the lead screw 92, and the rolling elements 98' are arranged between the drive nut 90" and the lead screw 92. In the example shown, the rolling elements 98' include rollers. Thus, the driver 24" can be considered as a roller screw. The rolling elements 98' support the drive nut 90" relative to the screw 92 so that the drive nut 90" does not contact the screw 92. The rolling elements 98' are arranged circumferentially and symmetrically around the screw 92. The roller shaft 146 extends between and connects the pair of end rollers 144. Therefore, each rolling element 98' can include an end roller 144 located at a first end of the shaft 146, and can also include an end roller 144 located at a second end of the roller shaft 146. In some examples, the roller shaft 146 includes a thread that is configured to cooperate with the screw thread 110 to apply a driving force to the screw 92. Each end roller 144 includes teeth. The end roller 144 extends between the thread 110 and the drive ring 142 and engages with the thread 110 and the drive ring 142. The teeth of the end roller 144 engage with the teeth of the drive ring 142.

[0084] The drive nut 90″ includes a first drive ring 142 located at a first end of the drive nut 90″ and a second drive ring 142 located at a second end of the drive nut 90″. For each rolling element 98′, a first one of the end rollers 144 engages with the teeth of the drive ring 142 located at the first end of the drive nut 90″, and a second one of the end rollers 144 engages with the teeth of the drive ring 142 located at the second end of the drive nut 90″. As the drive nut 90″ rotates, the engagement between the end rollers 144 and the drive ring 142 causes each rolling element 98′ to rotate about its own axis and causes the array of rolling elements 98′ to rotate about the pump axis PA-PA. The threads of the roller shaft 146 engage with the screw threads 110 and apply a driving force to the screw threads 110 to linearly displace the screw 92.

[0085] The drive nut 90" rotates relative to the lead screw 92 and causes the rolling elements 98' to apply an axial force to the lead screw 92 to linearly drive the lead screw 92. The driver 24" thereby converts a rotational input into a linear output.

[0086] Figure 7 is a block diagram of pump 10. Fluid displacer 20, motor 22, driver 24, controller 26, and user interface 27 are shown. Motor 22 includes stator 28 and rotor 30. Controller 26 includes control circuitry 31 and memory 33.

[0087] The motor 22 is disposed within the pump body (e.g., pump body 16), and in the example shown, the motor 22 is coaxial with the fluid displacer 20. The controller 26 is operatively connected, communicatively connected, and / or electrically connected to the motor 22 to control the operation of the motor 22. The controller 26 is configured to regulate the delivery of electrical energy to the electric motor 22 in order to control the operation and pumping of the pump 10. Although the motor 22 and the fluid displacer 20 are shown as being coaxial, it should be understood that in some examples, the rotor 30 can be configured to rotate on a motor axis that is not coaxial with the reciprocating axis of one or more fluid displacers 20. In addition, each fluid displacer 20 can be configured to reciprocate on its own reciprocating axis that is not coaxial with the reciprocating axis of another fluid displacer 20. It should also be understood that although the pump 10 is shown as including two fluid displacers 20, some examples of the pump 10 may include a single fluid displacer 20 or more than two fluid displacers 20.

[0088] The position sensor 62 is configured to generate information about the operation of the pump 10 and the position of the fluid displacer 20. In some examples, the position sensor 62 can be configured as a rotary position sensor configured to generate information about the rotational position of the rotor 30. For example, the position sensor 62 can be arranged adjacent to the rotor 30 and configured to sense the rotation of the rotor 30 and generate data in response to the rotation. In some examples, the position sensor 62 includes a Hall effect sensor array arranged adjacent to the rotor 30 to sense the polarity of the permanent magnets forming the permanent magnet array of the rotor 30. The controller 26 can commutate the motor 22 based on the data generated by the position sensor 62. The position sensor 62 can generate data about the permanent magnet and provide commutation information to the controller 26. In some examples, the position sensor 62 can be configured to directly sense the linear displacement and / or position of the fluid displacer 20. For example, the position sensor 62 can be configured to sense the linear displacement of the fluid displacer 20 and / or the lead screw 92.

[0089] The position sensor 62 can be configured to count the magnetic segments of the rotor 30 as the permanent magnet passes through the position sensor 62, and each magnet is detected when the magnetic field measured by the position sensor 62 increases to above a threshold and then decreases back below the threshold, the threshold corresponding to the position sensor being close to the magnet. The controller 26 can be configured to know how many times the magnetic segment passes through corresponds to how many angular displacements of the rotor 30, how many full turns of the rotor 30, how many linear displacements of the lead screw 92 (and the fluid shifter 20), and / or how many parts of the pump cycle, among other options. The position sensor 62 may not provide information about the rotational direction in which the rotor 30 turns, but the controller 26 knows in which direction the rotor 30 is driven. The controller 26 can then determine the position of the lead screw 92 and / or the fluid shifter 20 along the pump axis PA based on the count of the number of times the magnet passes through the position sensor 62. In some examples, when the rotor 30 is driven in a first direction (e.g., one of clockwise and counterclockwise), the number of times the magnet passes is added to the cumulative total, and when the rotor 30 is driven in an opposite direction (e.g., the other of clockwise and counterclockwise), the number of times the magnet passes is subtracted from the cumulative total.

[0090] The motor 22 is a reversible motor in which the stator 28 can rotate the rotor 30 in either direction of two rotational directions. The rotor 30 is connected to the fluid displacer 20 via a driver 24, which receives the rotational output from the rotor 30 and provides a linear input to the fluid displacer 20. The driver 24 causes the fluid displacer 20 to reciprocate along the pump axis PA. The driver 24 can be any desired configuration for receiving the rotational output from the rotor 30 and providing a linear input to one or both of the fluid displacers 20.

[0091] Rotating the rotor 30 in a first rotational direction causes the driver 24 to displace the fluid displacer 20 in a first axial direction. Rotating the rotor 30 in a second rotational direction causes the driver 24 to displace the fluid displacer 20 in a second axial direction opposite the first axial direction. The driver 24 is directly connected to the rotor 30, and the fluid displacer 20 is directly driven by the driver 24. Thus, the motor 22 directly drives the fluid displacer 20 without an intermediate transmission (e.g., a reduction transmission).

[0092] The fluid displacer 20 may be of any type suitable for pumping fluid from the inlet manifold 12 to the outlet manifold 14. For example, the fluid displacer 20 may include a piston, a diaphragm, or any other type suitable for reciprocating motion to pump fluid. It should be understood that while the pump 10 is described as including a plurality of fluid displacers 20, some examples of the pump 10 include a single fluid displacer 20 or more than two fluid displacers 20.

[0093] Controller 26 is configured to store software, implement functions and / or process instructions. Controller 26 is configured to perform any function described herein, including receiving output from any sensor cited herein, detecting any condition or event cited herein, and controlling the operation of any component cited herein. Controller 26 can be any suitable configuration for controlling the operation of motor 22, collecting data, processing data, etc. Controller 26 can include hardware, firmware and / or stored software, and controller 26 can be installed on one or more circuit boards in whole or in part. Controller 26 can be any type suitable for operating according to the technology described herein. Although controller 26 is illustrated as a single unit, it should be understood that controller 26 can be arranged across one or more circuit boards. In some examples, controller 26 can be implemented as multiple discrete circuit sub-assemblies.

[0094] The memory 33 is configured to store software that, when executed by the control circuit 31, controls the operation of the motor 22. The control circuit 31 may include one or more of the following: a microprocessor, a controller, a digital signal processor (DSP), an application specific integrated circuit (ASIC), a field programmable gate array (FPGA), or other equivalent discrete or integrated logic circuits. In some examples, the memory 33 is described as a computer-readable storage medium. In some examples, the computer-readable storage medium may include a non-transient medium. The term "non-transient" may mean that the storage medium is not embodied as a carrier or propagating signal. In some examples, the non-transient storage medium may store data that may change over time (e.g., in RAM or cache). In some examples, the memory 33 is a temporary memory, which means that the main purpose of the memory 33 is not long-term storage. In some examples, the memory 33 is described as a volatile memory, which means that when the power to the controller 26 is turned off, the memory 33 does not maintain the stored content. Examples of volatile memory may include random access memory (RAM), dynamic random access memory (DRAM), static random access memory (SRAM), and other forms of volatile memory. In one example, the memory 33 is used by software or applications running on the control circuit 31 to temporarily store information during program execution. In some examples, the memory 33 also includes one or more computer-readable storage media. The memory 33 can also be configured to store information for a long time. The memory 33 can be configured to store a larger amount of information than a volatile memory. In some examples, the memory 33 includes a non-volatile storage element. Examples of such non-volatile storage elements can include a magnetic hard disk, an optical disk, a flash memory, or an electrically programmable memory (EPROM) or an electrically erasable programmable (EEPROM) memory.

[0095] The user interface 27 may be any graphical and / or mechanical interface that enables a user to interact with the controller 26. For example, the user interface 27 may implement a graphical user interface displayed at a display device of the user interface 27 for presenting information to the user and / or receiving input from the user. The user interface 27 may include graphical navigation and control elements, such as graphical buttons or other graphical control elements presented at the display device. In some examples, the user interface 27 includes physical navigation and control elements, such as physically actuated buttons, dials, switches, sliders, knobs, or other physical navigation and control elements. In general, the user interface 27 may include any input and / or output devices and control elements that enable a user to interact with the controller 26.

[0096] The pump 10 can be controlled based on any desired output parameter. In some examples, the pump 10 is configured to provide a process fluid flow based on a desired pressure, flow rate, and / or any other desired operating parameter. In some examples, the pump 10 is configured so that a user can control the operation of the pump 10 based on the operating capacity of the pump 10. For example, a user can set the pump 10 to operate at 50% capacity, during which a target operating parameter such as speed, pressure, flow rate, etc. is half of the maximum value of the operating parameter. In some examples, the pump 10 does not include a fluid sensor, such as a pressure sensor or a flow sensor. In some examples, a pumping system including the pump 10 does not include a fluid sensor disposed downstream of the pump 10. In some examples, the pumping system does not include a fluid sensor disposed upstream of the pump 10.

[0097] The controller 26 controls the operation of the pump 10 so as to drive the fluid displacer 20 to reciprocate at a target speed and output fluid at a target pressure. The pump 10 may include a closed-loop speed control based on data provided by one or more position sensors 62. The position sensor 62 may be configured to sense the rotation of the rotor 30, and the rotational speed of the rotor 30 may be determined based on data from the position sensor 62. The rotational speed may provide an axial displacement speed of the fluid displacer 20. Therefore, the position sensor 62 may also be considered to form a speed sensor. The ratio of the rotational speed to the axial speed may be known based on the configuration of the driver 24. When a driver with a lead screw is used, such as a driver 24 with a lead screw 92, the axial speed is a function of the rotational speed of the rotor 30 and the lead of the thread of the lead screw 92. The controller 26 may operate the pump 10 so that the actual speed does not exceed the target speed. The speed of the fluid displacer 20 corresponds to the flow rate output by the pump 10. Therefore, a higher speed provides a higher flow rate, while a lower speed provides a lower flow rate.

[0098] The position of the fluid displacer 20 along the axis PA can be determined based on information generated by the position sensor 62, based on directly sensing the displacement / position of the fluid displacer 20 or the driver 24, or based on directly sensing the rotational displacement / position of the rotor 30. The ratio of the rotational speed of the rotor 30 to the axial displacement speed of the fluid displacer 20 is known, so that the speed of the fluid displacer 20 can be determined based on the rotational speed of the rotor 30. The axial displacement of the fluid displacer 20, and therefore the position along the axis of the fluid displacer 20, can be determined based on the known position of the fluid displacer 20 and the displacement speed of the fluid displacer 20. The controller 26 can be configured to control the operation of the pump 10 based on the position of the fluid displacer 20 within the pump cycle, as discussed in more detail below.

[0099] The controller 26 controls the pressure output of the pump 10 by controlling the delivery of electrical energy to the pump 10. The motor 22 can be controlled based on the maximum drive current. The controller 26 is configured to control the operation of the motor 22 so that the maximum drive current is not exceeded, which may be either the maximum operating current that the motor 22 can handle, or a target operating current associated with a target output parameter (e.g., target speed, pressure, flow, etc.). The controller 26 current limits the pump 10 so that the current applied to the motor does not exceed the maximum drive current. The current provided to the motor 22 controls the torque output by the motor 22, thereby controlling the pressure and flow output by the pump 10.

[0100] In some examples, the controller 26 is configured to determine the maximum drive current based on inputs to the controller 26 and based on operating conditions of the motor 22. For example, the target operating current can be determined based on the input voltage and the target speed. In some examples, the target operating current is determined based on the motor temperature in addition to the input voltage and the target speed. In some examples, the controller 26 is configured to determine the target operating current based on a three-dimensional table, wherein the target operating current is determined based on each of the input voltage, the target speed, and the motor temperature. It should be understood that the target operating current can change during operation as the operating parameters of the motor 22 change (e.g., the temperature of the motor 22 changes during operation). For example, the target operating current can increase as the temperature of the motor 22 increases, and can decrease as the temperature of the motor 22 decreases.

[0101] The target output parameters of the pump 10 may be provided to the controller 26 via the user interface 27. For example, a user may input the target parameters via one or more interfaces in the user interface 27. The user may provide input settings to the controller 26 via the user interface 27 to set the target output of the pump 10. For example, the user may provide an input pressure setting to set the target output pressure, the user may provide an input flow rate setting to set the target output flow rate, etc. The input settings are provided to the controller 26, and the controller 26 controls the operation of the pump 10 based on the input settings.

[0102] In some examples, the target parameter is set by a single input to the controller 26. For example, the user interface 27 may include a parameter input that provides a pressure and / or speed command to the controller 26. For example, the user interface 27 may be or include a knob that the user can adjust to set the operating parameters of the pump 10, the knob forming the parameter input. However, it should be understood that the parameter input may be any desired configuration, including analog or digital sliders, scales, buttons, knobs, dials, etc. Adjusting the parameter input may provide multiple parameter commands to the controller 26 to set multiple target parameters. When setting / adjusting the input, the parameters (e.g., pressure and speed) may be linked together to change in proportion to each other. For example, adjusting the parameter input to increase the target pressure may also increase the target speed, while adjusting the parameter input to reduce the target pressure may also reduce the target speed. Thus, one input may result in changes in both the pressure threshold and the speed threshold. The user may thus provide a single input to the controller 26 through the parameter input to adjust both the pressure and speed at a single moment in time.

[0103] During operation, the controller 26 regulates the delivery of electrical energy to the stator 28 to drive the rotation of the rotor 30. The controller 26 may provide a maximum drive current and drive the rotation of the rotor 30 to a target operating speed. The controller 26 may control the voltage to control the speed of the rotor 30. The current flowing through the motor 12 determines the torque applied to the rotor 30, thereby determining the pressure output by the pump 10. If the target operating speed is reached, the controller 26 continues to provide current to the motor 22 to operate at the target operating speed. If the maximum drive current is reached, the motor 22 may continue to operate at the maximum drive current regardless of the actual speed.

[0104] During operation, the controller 26 can axially position one or more fluid displacers 20 and manage the stroke length of the fluid displacer 20. As discussed above, the axial displacement rate of the fluid displacement member 20 is a function of the rotation rate of the rotor 30. In the example including the lead screw 92, the axial displacement rate is a function of the rotation rate of the lead screw 92 and the lead of the thread. In some examples, the pump 10 does not include an absolute position sensor for providing the axial position of the reciprocating component. Therefore, the controller 26 can axially position the reciprocating component based on information other than directly sensing the axial position. However, it should be understood that in other examples, the pump 10 may include a position sensor configured to directly generate information about the axial position of the fluid displacer 20.

[0105] When the system starts running, the controller 26 can operate in the starting operation mode. In some examples, the controller 26 causes the pump 10 to operate according to the startup routine when the system starts running. The pump 10 may be dry initially and needs to be started in order to operate effectively. During the startup routine, the controller 26 adjusts the speed of the pump 10 to facilitate effective startup. For example, the controller 26 can control the speed of the pump 10 based on the startup speed. The startup speed can be stored in the memory 274 and called back for the startup routine. The startup speed can be based on the target speed set for the pump 10, or it can be disconnected from the target speed. The controller 26 is based on the startup speed to prompt the pump 10 to operate to start the pump 10. After the startup routine is completed, the controller 26 exits the startup routine and resumes normal control of the motor 12. For example, after exiting the startup routine, the controller 26 can control the speed based on the target speed instead of the startup speed. The controller 26 can be configured to exit the startup routine based on any desired parameters. For example, controller 26 may be configured to exit the startup routine based on a threshold time, number of revolutions of rotor 30, number of pump cycles or strokes, current draw of motor 12, etc. In some examples, controller 26 may actively determine when to exit the startup routine, such as controller 26 exiting the startup routine based on the current draw of motor 12. For example, controller 26 may determine that pump 10 has been primed based on an increase in current draw or a spike in current, which indicates that pump 10 is pumping against pressure.

[0106] The controller 26 is configured to adjust the electrical energy to the motor 22 based on the pump 10 operating in the startup mode and the pump 10 operating in the pumping mode. The controller 26 is configured to adjust the electrical energy to the motor 22 so that the fluid displacer 20 moves differently in the startup mode than in the pumping mode. The different movement profiles of the fluid displacer 20 in the startup mode facilitate the startup of the pump 10. Then, once the pump 10 is started, the controller 26 can exit the startup mode and enter the pumping mode to pump the process fluid. The different movement profiles during the startup mode can include different target speeds, different acceleration rates, different deceleration rates, different stroke lengths, different movements through conversion, and other options related to the pumping mode.

[0107] The controller 26 is configured to regulate electrical energy to the motor 22 to displace the fluid displacer 20 through a pump cycle. A pump cycle can be considered to include: a first stroke along the pump axis PA in a first direction; a second stroke along the pump axis PA in a second direction opposite to the first direction; a first transition at which the fluid displacer 20 reverses direction from the first stroke to the second stroke; and a second transition at which the fluid displacer 20 reverses direction from the second stroke to the first stroke. The transition point is the location at which the fluid displacer 20 stops moving in the stroke direction and then reverses movement in the other direction from that point.

[0108] The pump cycle may additionally or alternatively be considered to include a pumping stroke phase, a suction stroke phase, and a transition phase, which occurs at each transition between the pumping stroke phase and the suction stroke phase, wherein the fluid displacer 20 reverses direction. The transition phase occurs in the transition from the pumping stroke phase to the suction stroke phase, and in the transition from the suction stroke phase to the pumping stroke phase.

[0109] In some examples, the controller 26 is configured to automatically transition between the startup mode and the pumping mode. During the startup mode, the motor 22 moves the fluid displacer 20 relatively quickly during the suction stroke phase and the pumping stroke phase, but slows down and / or pauses during the transition phase. In addition, in the pumping mode, the motor 22 can move the fluid displacer 20 relatively slowly (compared to the speed in the suction stroke phase and the pumping stroke phase in the startup mode) through the suction stroke phase and the pumping stroke phase, without the slowdown or pause in the startup mode during the transition phase, wherein this overall slower and steadier movement through the stroke in the pumping mode helps avoid unnecessary pulsation of the pumped fluid.

[0110] In some examples, the transition phase can be considered to occur from deceleration as the fluid displacer 20 moves in a first direction along the reciprocating axis until the fluid displacer 20 begins to accelerate along the reciprocating axis in a second direction opposite to the first direction. Thus, the transition phase can begin from deceleration to the transition point and until the fluid displacer 20 moves out of the transition point to the next opposite stroke.

[0111] In some examples, the conversion phase can be considered to occur in the terminal portion of the stroke. For example, the conversion phase can be considered to occur in the last 20% of a stroke before the fluid shifter 20 stops. In some examples, the conversion phase can be considered to occur in the last 15%, 10%, or 5% of the total stroke distance of the stroke. Therefore, the conversion phase can be a portion of a stroke until the conversion point. In some such examples, the conversion phase can be considered to occur in the last portion of the stroke and until the fluid shifter is driven to move in the opposite axial direction through the subsequent stroke.

[0112] The controller 26 is configured to cause the fluid displacer 20 to move differently when operating in the startup mode than when operating in the pumping mode. The different movement of the fluid displacer 20 in the startup mode facilitates effectively exhausting air from the fluid chamber 34 to prime the pump 10 with process fluid. The different movement of the fluid displacer 20 in the startup mode can help exhaust air from the fluid chamber 34 for each stroke of the fluid displacer 20, can help seat the check valve 58 at the time of the transition to help exhaust air from the fluid chamber 34 during subsequent strokes, and so on.

[0113] During startup, only gravity can close the check valve 56 because when the pump 10 is not primed, air flow within the pump does not meaningfully move the valve member (e.g., ball), and air loss through the closed check valve 56 is a significant setback when attempting to start. When the pump 10 is primed, the process fluid can more reliably close the check valve 56, making a pause or slowdown during the transition unnecessary. Therefore, slowing down or pausing during the transition phase at startup gives the check valve 56 more time to close.

[0114] In some examples, the controller 26 is configured to adjust the power delivery to the motor 22 to slow or pause the movement of the rotor 30, and thus adjust the fluid displacer 20 in the transition phase when operating in the starting mode. For example, the controller 26 can be configured to cause the fluid displacer 20 to purposefully pause movement and remain in the transition phase for a longer period of time when operating in the starting mode than when operating in the pumping mode.

[0115] In some examples, the controller 26 is configured to regulate the delivery of electrical energy to the electric motor 22 to cause a changeover lag between a changeover phase during the starting mode and a changeover phase during the pumping mode. The changeover lag is the time difference between a first time period when the changeover phase occurs in the starting mode and a second time period when the changeover phase occurs in the pumping mode. For example, if the changeover phase during the pumping mode takes two seconds and the changeover phase during the starting mode takes four seconds, the changeover lag is equal to the two-second difference between the changeover phases of the two modes. The controller 26 can regulate the energy delivered to the motor 22 so that the changeover phase takes a longer time period during the starting phase than during the pumping phase.

[0116] The controller 26 can be configured to implement the switching hysteresis by purposefully stopping the movement of the fluid displacer 20. Additionally or alternatively, the controller 26 can be configured to implement the switching hysteresis by a change in the deceleration rate of the fluid displacer 20 as the fluid displacer 20 approaches the switching point. For example, the controller 20 can cause the fluid displacer 20 to decelerate at a slower rate and a greater axial distance when operating in the starting mode compared to the pumping mode. Such a change in the deceleration rate can result in switching hysteresis, whether the switching stage is determined based on a portion of the stroke or based on the start of the deceleration.

[0117] This purposeful stopping of the movement of the fluid displacer 20 can be particularly useful during the startup phase because it allows the check valve 56 to close more reliably. As indicated by the switching hysteresis, the lower speed through the switching phase can be less than the speed at which the controller 26 and motor 22 can move the actuator 24 and the fluid displacer 20 without impact or other damage. The slower speed during the switching phase in the startup mode compared to the pumping mode can be less than the speed at which the controller 26 is programmed to move the rotor 30 and the fluid displacer 20 in the switching phase (and / or the pumping phase and the suction phase) when in the pumping mode.

[0118] The transition hysteresis and / or purposeful pause of the fluid displacer 20 provides time for the check valve 56 to close. Allowing the inlet check valve 56 to close during the transition phase between the suction stroke phase and the pumping stroke phase prevents air flow from the pumping chamber 34 from flowing back into the inlet manifold 12, which would otherwise inhibit priming. Allowing the outlet check valve 56 to close during the transition phase between the pumping stroke phase and the suction stroke phase prevents air flow from the output manifold 14 from flowing back into the pumping chamber 34, which would otherwise inhibit priming.

[0119] The pause in motion may be a programmed stop of movement of the rotor 30 for a period of time (e.g., between half a millisecond and 1000 milliseconds; or between one millisecond and 500 milliseconds; but other ranges are possible), rather than a momentary stop in movement of the rotor 30 and fluid displacer 20, which may be inherent, for example, when reversing direction during pumping mode. To achieve such a pause, the motor 22 may not be energized (e.g., not energized at all or only insufficiently energized) to drive movement, or the motor 22 may be energized to simply hold position and resist movement due to pressure in the fluid chamber 34.

[0120] For example, during a transition phase when not in the start-up mode, the controller 26 may energize the motor 22 to rotate the rotor 30 in a first direction with a first drive energy profile, and then reverse the flow of energy and / or phase to cause the direction of movement to reverse toward a second direction by delivering a second drive energy profile while the rotor 30 is rotating in the first direction. The controller 26 may adjust the energy delivery so that the second drive energy profile continues to be provided when the rotor 30 reverses direction and then rotates in the second direction. Thus, the second drive energy profile may cause the rotor 30 to decelerate to a stop when rotating in the first rotational direction, and may cause the rotor 30 to accelerate in the second rotational direction and exit the transition.

[0121] Continuing with this example, during the transition phase in the start-up mode, the controller 26 may energize the motor 22 to rotate the rotor in a first direction with a first drive energy profile, and then reverse the flow of energy and / or phase to cause the direction of movement to reverse toward a second direction by delivering a second drive energy profile while the rotor is rotating in the first direction, until the rotor is near a stop or completely stopped, in which state no motive energy is delivered to the motor, or a third energy profile is delivered to keep the rotor 30 stationary. The controller 26 may then resume delivering the second drive energy profile (or a similar motive energy profile) to accelerate the rotor 30 to rotate in the second rotational direction, and accelerate out of the transition and into a subsequent stroke.

[0122] In some examples, when pausing during a transition in the start-up mode, the controller 26 may reduce energy to the motor to allow the rotor 30 and fluid displacer 20 to float (e.g., be moved by the fluid under pressure), or the controller 26 may deliver sufficient energy to cause the rotor 30 to electromagnetically hold its position against back pressure during the pause.

[0123] In addition to or in lieu of implementing a slowdown or pause during the transition, the controller 26 can control the displacement speed of the fluid displacer 20 in both the startup mode and the pumping mode. In some examples, the controller 26 is configured to control the displacement speed of the fluid displacer 20 during the startup mode and the pumping mode, so that the fluid displacer 20 moves differently in the startup mode than in the pumping mode. The controller 26 can be configured to control the movement of the fluid displacer 20 based on a pumping speed set point when operating in the pumping mode. The pumping speed set point sets the desired rotational speed of the rotor 30, and thereby sets the linear displacement speed of the fluid displacer 20 during pumping. The controller 26 is configured to accelerate the fluid displacer 20 to a speed associated with the pumping speed set point while the fluid displacer 20 moves through the pumping stroke stage and the suction stroke stage. The pumping speed set point can be set based on an input setting provided by a user at the user interface 27, such as a desired flow rate, pressure, etc. input by the user. The controller 26 is configured to accelerate the rotor 30 / fluid displacer 20 to a speed associated with the pumping speed set point and move at that speed until decelerating to a transition point when operating in the pumping mode.

[0124] The controller 26 can also be configured to control the movement of the fluid displacer 20 based on a start-up speed set point when operating in the start-up mode. The start-up speed set point sets the desired rotational speed of the rotor 30, and thereby sets the linear displacement speed of the fluid displacer 20 during start-up. The start-up speed set point can be set based on the pumping speed set point. The start-up speed set point can be associated with the pumping speed set point (e.g., 1.1 times the pumping speed set point; 1.5 times the pumping speed set point; 2.0 times the pumping speed set point; etc.), so that changes in the pumping speed set point will cause changes in the start-up speed set point. Therefore, the start-up speed set point can also be considered to be set based on the input setting provided at the user interface 27.

[0125] The start-up speed set point is associated with a higher speed than the pumping speed set point, so that the controller 26 causes the fluid displacer 20 to move faster during the suction stroke phase and the pumping stroke phase during the start-up mode (compared to the relatively slower movement during the pumping stroke phase and the suction stroke phase in the pumping mode). The (start-up or pumping) speed set point is associated with the maximum speed during the pumping stroke phase and the suction stroke phase. The controller 26 can be considered to drive through the stroke phase at a constant speed, where the constant speed is greater in the start-up mode than in the pumping mode. The constant speed can be a target speed associated with the speed set point. The faster speed of the fluid displacer 20 when in the start-up mode enhances air compression during startup (however, when pumping incompressible fluids, this compression is not a factor and is therefore not beneficial when not starting), and thus enhances the exhaust of air from the fluid chamber 34.

[0126] In some examples, the controller 26 can be considered to implement a stroke hysteresis between the time required to complete a stroke when operating in the pumping mode and the time required to complete a stroke in the starting mode. The time for completing a stroke can be the time from the start of acceleration in a direction along the axis PA to the time when the fluid displacer 20 stops moving in that direction. In the case where the starting speed set point is greater than the pumping speed set point, the fluid displacer 20 can move through the stroke faster when operating in the starting mode than when operating in the pumping mode. The stroke hysteresis is the difference in the time required to complete the stroke in each mode. For example, if a stroke takes 1.0 seconds in the starting mode and 1.2 seconds in the pumping mode, the stroke hysteresis is -0.2 seconds.

[0127] In addition to or in lieu of slowing down or pausing during transitions in the priming mode and moving the fluid displacer 20 through the stroke at a higher speed in the priming mode, the controller 26 may control the displacement distance of the fluid displacer 20 so that the fluid displacer 20 moves differently in the priming mode than in the pumping mode. Figure 8 As shown, the fluid shifter 20 is configured to switch at the switching point CP1 when operating in the pumping mode and start to move in the opposite axial direction. The fluid shifter 20 is configured to switch at the switching point CP2 when operating in the start-up mode and start to move in the opposite axial direction. The switching points CP1 and CP2 are the positions along the axis where the fluid shifter 20 stops shifting in the first axial direction and starts shifting in the second axial direction. For example, the switching points CP1 and CP2 can be the positions where the fluid shifter 20 completes the pumping stroke and switches to start the suction stroke. The relative axial positions of the switching points CP1 and CP2 along the pump axis PA can be stored in the memory 33. During the conversion, when the fluid displacement member 20 approaches the switching points CP1 and CP2, the controller 26 causes the motor 22 to start reversing so as to stop at the switching points CP1 and CP2 and start to accelerate in the opposite direction.

[0128] When operating in the pumping mode, the controller 20 is configured to cause the fluid displacer 20 to stop displacement in the first direction at a transition point CP1 and to turn and begin displacement in the second direction at the transition point CP1. The controller 26 is configured to change the transition point between the start-up mode and the pumping mode such that the transition point CP2 for the start-up mode is different from the transition point CP1 for the pumping mode. Figure 8As shown, the transition point CP2 is axially spaced from the transition point CP1. In the example shown, the transition point CP2 is a distance X farther along the axis PA than the transition point CP1. During the pumping stroke, the position to which the fluid displacer 20 is switched when operating in the starting mode is axially closer to the fluid cover 18 than the position to which it is switched when operating in the pumping mode. Compared with pumping in the pumping mode, when pumping in the starting mode, the fluid displacer 20 is axially closer to the fluid cover 18 increases the compression ratio, which is the ratio between the volume of the fluid chamber 34 at the end of the suction stroke of the fluid displacer 20 (when the fluid chamber 34 is at the maximum volume) and the volume of the fluid chamber 34 at the end of the pumping stroke of the fluid displacer 20 (when the fluid chamber 34 is at the minimum volume). Therefore, the compression ratio when operating in the starting mode can be greater than the compression ratio when operating in the pumping mode. The increased compression ratio is particularly useful when the discharge of compressible fluid (e.g., air) from the pumping chamber 34 occurs during startup. Thus, shifting the switching point from switching point CP1 to switching point CP2 when operating in the pumping mode facilitates faster and more efficient priming of the pump 10 .

[0129] As discussed above, the controller 26 can be considered to implement a stroke hysteresis between the pumping mode and the starting mode. The difference in displacement distance between the stroke in the pumping mode and the stroke in the starting mode can reduce the stroke hysteresis, or even eliminate the stroke hysteresis, because the fluid displacer 20 moves a greater axial distance through the stroke in the starting mode than through the stroke in the pumping mode. In some examples, the fluid displacer 20 moves through the stroke faster in the starting mode than in the pumping mode.

[0130] In some examples, controller 26 may be considered to implement a cycle hysteresis between a pump cycle in pumping mode (including a full suction stroke and a full pumping stroke) and a pump cycle in priming mode. Cycle hysteresis is the difference in time required to complete a full pump cycle in priming mode compared to pumping mode.

[0131] In some examples, the cycle hysteresis can be different from (e.g., greater than or less than) the transition hysteresis. For example, the cycle hysteresis can be less than the total transition hysteresis of the pump cycle, such as due to the increased speed of the fluid displacer 20 during the startup mode compared to the pumping mode. The pump cycle includes two transitions, the first transition from the pumping stroke to the suction stroke, and the second transition from the suction stroke to the beginning of the pumping stroke of the next pump cycle. If the fluid displacer 20 moves the same distance and speed during both the pumping stroke and the suction stroke, the cycle hysteresis will be equal to the total transition hysteresis of the pump cycle, which may be the case in some examples. However, in other examples, due to different speeds between the pumping mode and the startup mode, the cycle hysteresis is less than the total transition hysteresis.

[0132] Cycle hysteresis may be increased due to the transition hysteresis of the pump cycle, but may be reduced due to the increased speed at which the fluid displacer 20 moves through the stroke in the priming mode relative to the pumping mode. Cycle hysteresis may be further increased due to the increased length of each stroke in the priming mode compared to the pumping mode. In some examples, the increased stroke length distance may offset the speed difference.

[0133] In some examples, the increased stroke length distance can increase the cycle hysteresis so that the cycle hysteresis is greater than the transition hysteresis, such as when the speed set point in both the pumping mode and the starting mode is the same, or when the increased speed in the starting mode cannot fully compensate for the increased stroke distance in the starting mode.

[0134] In some examples, the controller 26 can implement a different acceleration profile and / or deceleration profile when operating in the startup mode than when operating in the pumping mode. For example, the controller 26 can cause the rotor 30 and the fluid displacer 20 to accelerate faster in the startup mode than in the pumping mode. This acceleration can cause the fluid displacer 20 to reach maximum speed faster to complete the stroke faster. In some examples, the fluid displacer 20 can be accelerated more slowly out of the transition, thereby providing additional time for the check valve 56 to close before starting to move out of the transition, and generating less backflow if the check valve 56 is not fully closed.

[0135] In some examples, the controller 26 can cause the rotor 30 and the fluid displacer 20 to decelerate differently in the startup mode than in the pumping mode. For example, the controller 26 can cause the fluid displacer 20 to decelerate more slowly when operating in the startup mode than when operating in the pumping mode. The slower deceleration provides a greater distance for the fluid displacer 20 to decelerate. This longer axial distance for deceleration can help drive the compressible air from the fluid chamber 34 to start the pump 10.

[0136] The controller 26 can be configured to automatically transition between the startup mode and the pumping mode during operation of the pump 10. In some examples, the controller 26 can be configured to initially operate in the startup mode upon power-up or other start of pumping. In some examples, the controller 26 can be configured to initially operate in the pumping mode upon power-up or other start of pumping, and can transition to the startup mode based on the controller 26 determining that the pump 10 is not primed. For example, based on the current draw of the motor 22, etc., the state of the pump 10 can be sensed, such as being primed and therefore ready to pump in the pumping mode.

[0137] For example, the controller 26 may store a threshold current draw in the memory 33, and may compare the actual current draw of the motor 22 to the current draw threshold to determine whether the pump 10 is activated. The threshold current draw may vary depending on the input setting from the user. For example, for a relatively large target pressure, the threshold current draw may be larger. A current draw below the threshold may indicate that the pump 10 is not activated, while a current draw equal to or above the threshold may indicate that the pump 10 is activated. In some examples, an increase in current draw when operating in the activation mode may indicate that the pump 10 is pumping an incompressible fluid instead of air, thereby indicating that the pump 10 is activated. Therefore, even without a current draw threshold, an increase in current draw may indicate that the pump 10 is activated.

[0138] When priming is sensed, the controller 26 may transition to operating in the pumping mode (e.g., the fluid displacer 20 moves more slowly during the suction stroke phase and the pumping stroke phase compared to the speed during the priming mode; the strokes in the pumping mode are shorter compared to the priming mode; and / or the transition time for transitions in the pumping mode is shorter compared to the priming mode, etc.) Such changes may reduce pulsation when pumping in the pumping mode.

[0139] Loss of start may be detected by a reduction in current draw in motor 22, etc. In this case, controller 26 may return to start mode until start is sensed again, in which case controller 26 may transition back to pumping mode.

[0140] In some examples, the controller 26 is configured to exit the startup mode and operate in the pumping mode based on a parameter reaching a threshold value. As discussed above, the parameter may be an operating parameter of the motor 22, such as the current draw of the motor 22. In some examples, the parameter may be an output parameter of the pump 10, such as the pressure or flow of the fluid output by the pump 10. For example, the controller 26 may be configured to determine that the pump 10 is started based on the downstream fluid pressure reaching a pressure threshold value.

[0141] In some examples, the controller 26 is configured to switch between the startup mode and the pumping mode based on a time parameter. The time parameter can replace or be in addition to the sensed operating parameter (e.g., current draw, pressure, flow, etc.). For example, the controller 26 can be configured to exit the startup mode after being in the startup mode for a certain time count. The time count can be any desired time period, such as 15 seconds, 30 seconds, 45 seconds, 60 seconds, etc. In some examples, the controller 26 can be configured to exit the startup mode based on the controller 26 detecting that the pump 10 is pumping fluid (e.g., based on the current draw) or based on reaching a time threshold (whichever occurs first). The time threshold for exiting the startup mode can be considered to form an upper limit because the time threshold defines the maximum amount of time in the startup mode.

[0142] In some examples, the controller 26 is configured to implement a cool-down period after exiting the start-up mode and before re-entering the start-up mode. The cool-down period allows the controller 26 to have time to determine whether the pump 10 is being activated or has been activated. For example, the controller 26 can exit the start-up mode based on reaching a time threshold in the start-up mode. The controller 26 will then cause the pump 10 to operate in the pumping mode for a set period of time (e.g., 5 seconds, 7 seconds, 10 seconds, etc.) before re-entering the start-up mode. If the controller 26 determines that the pump 10 has been activated while in the pumping mode, the controller 26 will not re-enter the start-up mode, but will continue to operate in the pumping mode. The cool-down period, which is a time threshold, can be considered to form a lower limit because the cool-down period defines the minimum amount of time in the pumping mode after exiting the start-up mode.

[0143] In some examples, controller 26 exits the startup mode based on a count other than a time count. For example, controller 26 may be configured to exit the startup mode based on a pump stroke count reaching a stroke count threshold, based on a pump cycle count reaching a pump cycle threshold, etc.

[0144] The controller 26 causes the fluid displacer 20 to move differently in the startup mode than in the pumping mode. This different movement of the fluid displacer 20 in the startup mode facilitates exhausting air from the fluid chamber 34 for faster and more efficient startup. The controller 26 can cause the fluid displacer 20 to purposefully pause at the time of conversion before starting a subsequent stroke, thereby allowing the check valve 56 to close and preventing reverse flow that may inhibit startup. The controller 26 can additionally or alternatively cause the fluid displacer 20 to move faster through the stroke when in the startup mode, thereby reducing the time for startup, while slower movement during pumping reduces downstream pulsation. Additionally or alternatively, the controller 26 causes the fluid displacer 20 to move through a stroke having a larger axial length when in the startup mode, thereby increasing the compression ratio when in the startup mode, and providing a greater degree of exhaust of compressible air from the fluid chamber 34 when starting.

[0145] The controller 26 can automatically enter and exit the startup mode during operation of the pump 10. The controller 26 automatically enters the startup mode (e.g., based on the sensed current draw of the motor 22), which facilitates priming of the pump 10 without user interaction. Conversely, the controller 26 is configured to automatically prime the pump 10 when the controller 26 senses that the pump 10 is not primed. The controller 26 automatically enters the startup mode to facilitate efficient operation of the pump 10 without user interaction to cause priming. The controller 26 automatically exits the startup mode (e.g., based on the current draw or count), also facilitating efficient operation of the pump 10 without user interaction. The user does not have to affirmatively switch the pump 10 to the pumping mode, but the controller 26 will automatically enter the pumping mode to pump the process fluid.

[0146] Fig. 9A is a cross-sectional view of the pump 10 . Fig. 9B yes Fig. 9A The enlarged cross-sectional view of detail B in FIG. 1 shows the installation of a fluid displacer 200 for the pump 10 . Fig. 9C 2 is a cross-sectional view showing a fluid displacer 200 disassembled from the pump 10 and in a partially unassembled state relative to the driver 24. The fluid displacer 200 is substantially similar to the fluid displacer 20, except that the fluid displacer 200 includes a flexible body 202 of multiple parts. The fluid displacer 200 includes a flexible body 202, an inner plate 204, an outer plate 206, and a fastener 208. The flexible body 202 includes a main diaphragm 210 and a backing 212. The main diaphragm 210 includes a diaphragm body 214 and a flange 216. The backing 212 includes a backing body 218 and a flange cup 220. The pump body 16 includes a body groove 222. The fluid cover 18 includes a cover groove 224. The body groove 222 and the cover groove 224 together define a mounting groove 226.

[0147] The fluid displacer 200 is formed as a diaphragm that is configured to flex as the fluid displacer 200 moves through a pumping stroke and a suction stroke. The fluid displacer 200 is configured to move through a pumping stroke in an axial direction PS along a reciprocating axis RS (which may be coaxial with the pump axis PA), and through a suction stroke in an axial direction SS. The fluid displacer 200 includes an outer side 228 oriented toward the fluid chamber 34, and includes an inner side 230 oriented toward the motor 22 and the driver 24. The outer side 228 may also be referred to as a fluid-facing side. The inner side 230 may also be referred to as a motor-facing side.

[0148] The flexible body 202 is configured to flex as the fluid displacer 200 moves through a pumping stroke and a suction stroke. The flexible body 202 is at least partially located between the inner plate 204 and the outer plate 206. The outer plate 206 is disposed on an outer side 228 of the flexible body 202, and the inner plate 204 is disposed on an inner side 230 of the flexible body 202. The flexible body 202 can be clamped between the inner plate 204 and the outer plate 206. Fasteners 208 extend through the outer plate 206, the flexible body 202, and the inner plate 204 to connect the fluid displacer 200 to the driver 24. In the example shown, the fasteners 208 extend through the fluid displacer 200 and into the leadscrew 92 of the driver 24.

[0149] The main diaphragm 210 and the backing 212 are stacked together to form the flexible body 202. In the example shown, the main diaphragm 210 and the backing 212 are stacked but not fixed to each other. In the example shown, no adhesive fixes the main diaphragm 210 and the backing 212 together. The main diaphragm 210 and the backing 212 are stacked but not fixed together, allowing the flexible body 202 to be disassembled and one or the other of the main diaphragm 210 and the backing 212 to be replaced without replacing the other of the main diaphragm 210 and the backing 212.

[0150] The diaphragm body 214 extends radially outward from the reciprocating axis RA. The flange 216 is arranged at the outer radial edge of the diaphragm body 214. It should be understood that the main diaphragm 210 may include an additional portion extending radially outward from the flange 216, but not all examples are limited thereto. The flange 216 is annular and extends around the reciprocating axis RA. The flange 216 is enlarged relative to the diaphragm body 214. The flange 216 can be circular and other configurations. In some examples, since the inner axial portion of the flange 216 includes a recess for accommodating the backing 212, the outer axial portion of the flange 216 (facing the fluid cover 18) is formed more fully than the inner axial portion of the flange 216 (facing the pump body 16). Therefore, the flange 21 can protrude farther axially in the axial direction PS relative to the adjacent portion of the diaphragm body 214 than the flange 216 protrudes in the axial direction SS relative to the adjacent portion of the diaphragm body 214.

[0151] The backing body 218 extends radially outward from the reciprocating axis RA. The flange cup 220 is arranged at the outer radial edge of the backing body 218. It should be understood that the backing 212 may include additional portions extending radially outward from the flange cup 220, but not all examples are limited thereto. The flange cup 220 is open to receive the flange 216 therein. In the example shown, the flange cup 220 is open in the axial direction PS. Therefore, the flange cup 220 can be considered to be away from the driver 24 and open toward the fluid chamber 34. In the example shown, the flange cup 220 is closed toward the pump body 16 and open toward the fluid cover 18.

[0152] Backing 212 Fig. 9B and Fig. 9C 234 is shown in a non-flexed state. With the backing 212 in the non-flexed state, the backing 212 includes: a central portion 232 extending radially from the reciprocating axis RA, a groove 234 extending radially outward from the central portion 232, and a flange cup 220 arranged radially outward of the groove 234. The central portion 232 and the groove 234 form part of the backing body 218. The groove 234 is open in the axial direction SS and toward the motor 22. The groove 234 and the flange cup 220 are open in opposite axial directions along the reciprocating axis RA. The groove 234 is an annular groove 234, which extends annularly completely around the reciprocating axis RA. The opening of the flange cup 220 and the groove 234 in opposite axial directions facilitates the mating of the main diaphragm 210 and the backing 212, even without the use of adhesive.

[0153] With the main diaphragm 210 and the backing 212 stacked together, the flange 216 is arranged in the flange cup 220. The flange cup 220 does not completely surround the flange 216, and does not completely wrap around the flange 216. The body groove 222 is an annular recessed portion formed in the pump body 16. The cover groove 224 is an annular recessed portion formed in the fluid cover 18. With the fluid cover 18 assembled to the pump body 16, the body groove 222 is opposite to the cover groove 224, so that a mounting groove 226 is formed between the opposing body groove 222 and cover groove 224.

[0154] With the fluid displacer 200 assembled to the pump 10, the flexible body 202 is clamped between the pump body 16 and the fluid cover 18. The flange 216 and the flange cup 220 are disposed within the mounting groove 226 and are clamped between the pump body 16 and the fluid cover 18 within the mounting groove 226. In the example shown, the flange 216 does not directly contact the pump body 16. Instead, the flange cup 220 covers the portion of the flange 216 disposed in the body groove 222, so that the flange cup 220 is disposed between the flange 216 and the pump body 16, and the flange cup 220 contacts the pump body 16.

[0155] In the example shown, the main diaphragm 210 and the backing 212 are clamped together but not directly fixed to each other. In the example shown, the main diaphragm 210 and the backing 212 are clamped together at an inner annular interface 236 and an outer annular interface 238. The inner annular interface 236 is axially arranged between the inner plate 204 and the outer plate 206. The inner annular interface 236 clamps the inner portion of the main diaphragm 210 and the backing 212 together radially. The outer annular interface 238 is axially arranged between the fluid cover 18 and the pump body 16. The outer annular interface 238 is arranged in the mounting groove 226. The flexible body 202 is configured to flex at a position radially between the inner annular interface 236 and the outer annular interface 238 during pumping. Clamping the primary diaphragm 210 and the backing 212 together at the radially inner annular interface 236 and the radially outer annular interface 238 facilitates the backing 212 to support the primary diaphragm 210 at locations radially between the inner annular interface 236 and the outer annular interface 238 that form the flexure portion of the fluid displacer 200 .

[0156] The main diaphragm 210 is axially disposed between the backing 212 and the fluid chamber 34. In some examples, the main diaphragm 210 forms an outer side 228 of the fluid displacer 200 such that the main diaphragm 210 is exposed to and contacts the fluid being pumped through the fluid chamber 34 by the fluid displacer 200. It should be understood that not all examples are so limited. In some examples, a cover may be disposed over the main diaphragm 210 such that the cover, rather than the main diaphragm 210, contacts the process fluid during pumping.

[0157] The backing 212 is disposed axially between the main diaphragm 210 and the motor 22. The backing 212 is not exposed to and does not contact the process fluid pumped by the fluid displacer 200. The backing 212 may form an inner side 230 of the fluid displacer 200. The backing 212 may be exposed to a motor cavity 240 within the pump body 16, in which the motor 22 is disposed.

[0158] The main diaphragm 210 has a thickness T1. The thickness T1 is taken from the portion of the main diaphragm 210 located radially inward of the flange 216. The backing 212 has a thickness T2. The thickness T2 is taken from the portion of the backing 212 located radially inward of the flange cup 220. In some examples, the flange cup 220 has a thickness T2 that is the same or similar to the backing body 218. The thickness T1 is greater than the thickness T2, so that the main diaphragm 210 is thicker than the backing 212.

[0159] The backing 212 is configured to provide structural support to the main diaphragm 210 during operation of the pump 10. The backing 212 may be formed of a more resilient material than the main diaphragm 210 and inhibit wear of the main diaphragm 210 during operation.

[0160] In some examples, the main diaphragm 210 is formed of a first polymer and the backing 212 is formed of a second polymer. In some examples, the second polymer is different from the first polymer. For example, the main diaphragm 210 can be formed of polytetrafluoroethylene (PTFE). The backing 212 can be formed of thermoplastic vulcanizate (TPV). In some examples, the backing 212 is formed of fully cured ethylene propylene diene monomer (EPDM) rubber particles encapsulated in a polypropylene matrix. For example, the backing 212 can be formed of Santoprene® thermoplastic vulcanizate (available from Celanese) or other dynamically vulcanized alloys, which are mainly composed of fully cured EPDM rubber particles encapsulated in a polypropylene matrix.

[0161] In some examples, the second polymer is the same as the first polymer.For example, both the primary diaphragm 210 and the backing 212 may be formed from PTFE.

[0162] The backing 212 is configured to inhibit wear of the main diaphragm 210. As discussed above, the pump 10 is configured to mechanically displace the fluid displacer 200 through corresponding pumping strokes and suction strokes. When the fluid displacer 200 is pulled through the suction stroke (in the axial direction SS), the process fluid being pulled into the fluid chamber 34 acts on the fluid displacer 200 and can evenly apply force on the outer side 228 of the fluid displacer 200.

[0163] When the fluid displacer 200 is pushed (in the axial direction PS) through the pumping stroke, the driver 24 applies a driving force to the flexible body 202. The driver 24 mechanically displaces the fluid displacer 20 through the pumping stroke. The driver 24 applies a driving force to the central portion of the fluid displacer 20, while the process fluid in the pumping chamber 34 resists the movement of the fluid displacer 20 and applies a force to the outer side 228 of the fluid displacer 200. The fluid displacer 200 is located on the inner side 230. The portion of the inner plate 204 radially outward is not directly applied to these portions by the driver 24 to displace in the axial direction PS. This mechanical drive configuration can cause the fluid displacer 200 to fold on the inner plate 204, which may cause wear on the flexible body 202. This is different from an air-operated diaphragm pump, in which compressed air acts on the inner side of the diaphragm to drive the diaphragm through the pumping stroke. The compressed air in such a pump applies force uniformly over the radial extent of the diaphragm.

[0164] The backing 212 is disposed axially inwardly 230 (closer to the motor 22) of the fluid displacer 200, and in the example shown, forms the inner side 230 of the fluid displacer 200. The backing 212 is a portion of the fluid displacer 200 that can be folded over and in contact with the inner plate 204. The backing 212 provides rigidity to the fluid displacer 200 and is configured to disperse the force applied by the driver 24 radially outwardly on the fluid displacer 200. The backing 212 resists wear and prevents wear on the main diaphragm 210, thereby protecting the main diaphragm 210 and increasing the service life of the main diaphragm 210.

[0165] The fluid displacer 200 provides significant advantages. The flexible body 202 of the fluid displacer 200 is formed of a multi-part structure in which a main diaphragm 210 and a backing 212 are stacked together. The stacked configuration of the backing 212 on the inner side 230 of the flexible body 202 facilitates the backing 212 to support the main diaphragm 210 and reduce wear on the main diaphragm 210. This configuration is particularly useful when the fluid displacer 200 is mechanically displaced through a pumping stroke, in which the driving force is applied at a central location on the fluid displacer 200. The main diaphragm 210 and the backing 212 may not be fixed to each other (e.g., by an adhesive), so that one or the other of the main diaphragm 210 and the backing 212 can be removed and replaced without having to replace the other of the main diaphragm 210 and the backing 212.

[0166] Fig.10 2 is a cross-sectional view showing a fluid displacer 300 connected to the driver 24 but removed from the pump. The fluid displacer 300 is substantially similar to the fluid displacer 200, except that the main diaphragm 210 of the fluid displacer 300 is overmolded on the outer plate 206. The fluid displacer 300 also includes a cover 242, which is arranged on the main diaphragm 210 and can be fixed to the main diaphragm 210, for example, by an adhesive. The cover plate 242 is arranged on the axial side of the main diaphragm 210 opposite to the backing 212. The cover 242 can be formed of a polymer, such as the same polymer as the backing 212 or a different polymer from the backing 212. The cover 242 forms the outer side 228 of the flexible body 202 and is exposed to the process fluid. However, it should be understood that not all examples are limited to this. For example, the flexible body 202 may not include the cover 242, so that the main diaphragm 210 overmolded on the outer plate 206 is exposed to the process fluid. Backing 212 Fig.10 206 and the inner plate 204 are not spaced apart, but are fastened together to clamp the main diaphragm 210 and the backing 212 together. In the example shown, the groove 234 ( Fig. 9B and Fig. 9C ) are not shown, but the grooves 234 are shown when the backing 212 is in a non-flexed state.

[0167] Although the pumping assemblies in the present disclosure and claims are discussed in the context of dual displacement pumps, it should be understood that the pumping assemblies and controls can be used in a variety of fluid handling contexts and systems, and are not limited to those discussed. Any one or more of the pumping assemblies discussed can be used alone or with one or more additional pumps to transfer fluids for any desired purpose, such as position transfer, spraying, metering, application, etc.

[0168] Although the present invention has been described with reference to (one or more) exemplary embodiments, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for its elements without departing from the scope of the present invention. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the present invention without departing from the essential scope of the present invention. Therefore, it is intended that the present invention is not limited to the specific (one or more) embodiments disclosed, but that the present invention will include all embodiments falling within the scope of the appended claims.

Claims

1. A pump for pumping a fluid, the pump comprising: a first fluid chamber; a first inlet check valve and a first outlet check valve, the first inlet check valve and the first outlet check valve being positioned upstream and downstream of the first fluid chamber, respectively, and regulating flow into and out of the first fluid chamber; an electric motor including a stator and a rotor configured to generate a rotational output; a driver that converts the rotational output from the electric motor into linear reciprocating motion; a first fluid displacer configured to be driven by the driver at least partially to perform linear reciprocating motion within the first fluid chamber to pump the fluid, wherein the first fluid displacer reciprocates through a series of consecutive pump cycles, each pump cycle comprising a pumping stroke phase, a suction stroke phase, and a conversion phase, the conversion phase occurring at each transition between the pumping stroke phase and the suction stroke phase, during which the first fluid displacer reverses direction; and a controller configured to regulate energy delivery to the electric motor in a starting mode in which the pump is activated and in a pumping mode, and wherein the controller regulates energy delivery in the starting mode so that the rotor rotates to cause the first fluid displacer to move through a transition phase in the starting mode differently than in the pumping mode.

2. The pump according to claim 1, wherein The controller is configured to regulate the energy delivery to the electric motor so that the rotor rotates to cause the first fluid displacer to pause during a transition phase in the start-up mode to allow one or both of the first inlet check valve and the first outlet check valve to close.

3. The pump according to claim 2, wherein: The pause occurs at the point of reversal of direction such that the first fluid displacer moves along an axis in a first direction, stops in place for a period of time, and then moves along the axis in a second direction.

4. A pump according to any one of claims 2 to 3, wherein: The controller energizes the electric motor to maintain the position of the rotor during the pause so that the first fluid displacer can resist movement due to back pressure in the first fluid chamber.

5. A pump according to any one of the preceding claims, wherein The controller is configured to cause the motor to drive the fluid displacer to a first constant speed during one of the pumping stroke phase and the suction stroke phase when operating the pump in the startup mode.

6. The pump according to claim 5, wherein The controller is configured to cause the motor to drive the fluid displacer to a second constant speed during the other of the suction stroke phase and the pumping stroke phase in the start-up mode.

7. The pump according to claim 6, wherein The first constant speed is the same as the second constant speed.

8. The pump according to claim 5, wherein The controller is configured to cause the motor to drive the first fluid displacer to a second constant speed during one of the pumping stroke phase and the suction stroke phase when operating the pump in the pumping mode, and wherein the first constant speed is different from the second constant speed.

9. The pump according to claim 8, wherein The first constant speed is faster than the second constant speed.

10. The pump according to any one of claims 1 to 4, wherein The controller is configured to energize the electric motor to displace the first fluid displacer through one of the pumping stroke phase and the suction stroke phase based on a first speed set point in the start-up mode.

11. The pump according to claim 10, wherein The controller is configured to energize the electric motor to displace the first fluid displacer through one of the pumping stroke phase and the suction stroke phase based on a second speed set point in the pumping mode, the second speed set point being different from the first speed set point.

12. The pump according to claim 11, wherein The first speed set point is greater than the second speed set point.

13. A pump according to any one of the preceding claims, wherein The controller is configured to regulate the energy delivery to the electric motor so that the rotor rotates to cause the first fluid displacer to one or both pause in a transition phase during the start-up mode and move more slowly than in a transition phase during the pumping mode.

14. The pump according to claim 1, wherein The controller is configured to regulate the energy delivery to the electric motor so that the rotor rotates to move the first fluid displacer slower during the pumping phase and the suction phase during the pumping mode than the first fluid displacer moves during the pumping phase and the suction phase during the starting mode.

15. A pump according to any one of the preceding claims, wherein The controller is configured to exit the startup mode based on the sensed condition.

16. The pump according to claim 12, wherein: The sensed condition is an increase in current draw by the electric motor, indicative of pumping the fluid under pressure.

17. A pump according to any one of claims 1 to 14, wherein The controller is configured to exit the startup mode based on a parameter reaching a parameter threshold.

18. The pump according to claim 17, wherein The parameter is a sensed operating parameter of the pump.

19. The pump according to claim 18, wherein The sensed operating parameter is the current draw of the electric motor.

20. The pump of claim 17, wherein: The parameter is a time parameter.

21. A pump according to any one of claims 17 and 20, wherein The parameter threshold is based on a time count.

22. The pump of claim 17, wherein: The parameter threshold is based on a count of pump strokes.

23. The pump of claim 17, wherein: The parameter threshold is based on a count of pump cycles.

24. The pump of claim 1, wherein The controller moves the first fluid displacer such that, during a transition phase of the startup mode, the first fluid displacer at least one of pauses and moves slower than movement of the fluid displacer during a transition phase of the pumping mode.

25. A pump according to any one of the preceding claims, wherein The transition phase occurs from a deceleration along an axis in a first axial direction to an acceleration along the axis in a second axial direction, the second axial direction being opposite to the first axial direction.

26. A pump according to any one of claims 1 to 24, wherein The conversion phase reaches the last twenty percent of the stroke length of the displacement stroke.

27. A pump according to claim 26, wherein The conversion phase reaches the last fifteen percent of the stroke length.

28. A pump according to claim 27, wherein The conversion phase reaches the last ten percent of the stroke length.

29. The pump of claim 28, wherein The conversion phase reaches the last five percent of the stroke length.

30. A pump according to any one of the preceding claims, wherein The controller is configured to regulate energy delivery to the electric motor so that the rotor rotates to move the first fluid displacer at a first speed during the transition phase compared to each of the pumping stroke phase and the suction stroke phase, wherein the first speed is slower than a maximum speed at which the electric motor can move the first fluid displacer during the transition phase without causing a collision within the pump.

31. A pump according to any one of the preceding claims, wherein The controller is configured to adjust a stroke length of the first fluid displacer during the startup mode and during the pumping mode such that the first fluid displacer has a first stroke length during the startup mode and the fluid displacer has a second stroke length during the pumping mode.

32. A pump according to claim 31, wherein The first stroke length is different from the second stroke length.

33. A pump according to any one of claims 31 and 32, wherein The first stroke length is greater than the second stroke length.

34. A pump according to any one of claims 1 to 33, wherein The controller is configured to control the displacement of the first fluid displacer so that the first fluid chamber has a first compression ratio when the pump is in the starting mode and has a second compression ratio when the pump is in the pumping mode, the first compression ratio being different from the second compression ratio.

35. A pump according to claim 34, wherein The first compression ratio is greater than the second compression ratio.

36. A pump according to any one of the preceding claims, wherein The controller is configured to regulate the energy delivery to the electric motor such that a cycle hysteresis occurs between a pump cycle of the first fluid displacer in the start-up mode and a pump cycle of the first fluid displacer in the pumping mode.

37. A pump according to claim 36, wherein The cycle hysteresis is different from a transition hysteresis between a transition during the start-up mode and a transition during the pumping mode.

38. A pump according to claim 37, wherein The transition duration in the start-up mode is longer than the transition duration in the pumping mode.

39. A pump according to any of the preceding claims, further comprising a second fluid displacer, which is driven synchronously with the first fluid displacer by the driver, and the second fluid displacer performs linear reciprocating motion at least partially in the second fluid chamber through a series of continuous second pump cycles, each second pump cycle comprising a second pumping stroke phase, a second suction stroke phase, and a second conversion phase, the second conversion phase occurring at each transition between the second pumping stroke phase and the second suction stroke phase, and in the second conversion phase, the second fluid displacer reverses direction.

40. A pump according to any preceding claim, wherein The controller is configured to regulate energy delivery to the electric motor during a transition phase of the start-up mode such that the controller energizes the motor to cause the rotor to rotate in a first direction using a first drive energy profile, and then causes the rotor to rotate in a second direction opposite to the first direction by delivering a second drive energy profile while the rotor rotates in the first direction until the rotor approaches a stop or stops, in which state the controller regulates energy delivery to the electric motor such that no motive energy is delivered to the motor, or delivers a third energy profile to keep the rotor stationary, and then the controller resumes delivering the second drive energy profile to accelerate the rotor to rotate in the second direction.

41. A pump for pumping a fluid, the pump comprising: a first fluid chamber; a first inlet check valve and a first outlet check valve, the first inlet check valve and the first outlet check valve being positioned upstream and downstream of the first fluid chamber, respectively, and regulating flow into and out of the first fluid chamber; an electric motor including a stator and a rotor configured to generate a rotational output; a driver that converts the rotational output from the electric motor into linear reciprocating motion; a first fluid displacer configured to be driven by the driver at least partially to perform linear reciprocating motion within the first fluid chamber to pump the fluid, wherein the first fluid displacer reciprocates through a series of consecutive pump cycles, each pump cycle comprising a pumping stroke phase, a suction stroke phase, and a conversion phase, the conversion phase occurring at each transition between the pumping stroke phase and the suction stroke phase, during which the first fluid displacer reverses direction; and a controller configured to regulate energy delivery to the electric motor in a startup mode in which the pump is activated and in a pumping mode, wherein the controller regulates the energy delivery based on a target startup speed of the first fluid displacer in the startup mode and based on a target pumping speed of the first fluid displacer in the pumping mode, the target startup speed being greater than the target pumping speed.

42. A pump for pumping a fluid, the pump comprising: a first fluid chamber; a first inlet check valve and a first outlet check valve, the first inlet check valve and the first outlet check valve being positioned upstream and downstream of the first fluid chamber, respectively, and regulating flow into and out of the first fluid chamber; an electric motor including a stator and a rotor configured to generate a rotational output; a driver that converts the rotational output from the electric motor into linear reciprocating motion; a first fluid displacer configured to be driven by the driver to perform linear reciprocating motion along the axis and at least partially within the first fluid chamber to pump the fluid, wherein the first fluid displacer reciprocates through a series of consecutive pump cycles, each pump cycle comprising: a first stroke along the axis in a first direction, a second stroke along the axis in a second direction, a first transition of the first fluid displacer to reverse direction from the first stroke to the second stroke, and a second transition of the first fluid displacer to reverse direction from the second stroke to the first stroke; and A controller is configured to regulate energy delivery to the electric motor in a startup mode in which the pump is activated and in a pumping mode, wherein the controller regulates the energy delivery so that the first fluid displacer moves through a transition phase differently in the startup mode than in the pumping mode.

43. A pump according to claim 42, wherein The controller is configured to regulate the energy delivery to the electric motor so that the first fluid displacer moves a first distance along the axis through a first stroke in the starting mode, and the first fluid displacer moves a second distance along the axis through a first stroke in the pumping mode, the first distance being different from the second distance.

44. A pump according to claim 43, wherein The first distance is greater than the second distance.

45. A pump according to any one of claims 42 to 44, wherein The controller is configured to regulate the energy delivery to the electric motor so that the first fluid displacer is stationary at a first transition for a first time period in the starting mode and the first fluid displacer is stationary at the first transition for a second time period in the pumping mode, the first time period being different from the second time period.

46. ​​A pump according to claim 45, wherein The first time period is greater than the second time period.

47. A pump according to any one of claims 42 to 46, wherein The controller is configured to regulate the energy delivery to the electric motor based on a first speed set point in the starting mode and based on a second speed set point in the pumping mode, the first speed set point being different than the second speed set point.

48. A pump according to claim 47, wherein The first speed set point is associated with a higher speed than the second speed set point.

49. A pump according to any one of claims 42 to 48, wherein: The first stroke includes a pumping stroke phase and a first conversion phase occurring in a transition from the first stroke to the second stroke; The first transition phase occurs from the start of deceleration along the axis in the first direction to the start of acceleration along the axis in the second direction; and The second stroke includes a suction stroke phase and a second conversion phase occurring in a transition from the second stroke to the first stroke.

50. A pump according to any one of claims 42 to 48, wherein: The first stroke includes a pumping stroke phase and a first conversion phase occurring in a transition from the first stroke to the second stroke; The first conversion phase forms the last twenty percent of the length of the first stroke; and The second stroke includes a suction stroke phase and a second conversion phase occurring in a transition from the second stroke to the first stroke.

51. A pump according to any one of claims 42 to 48, wherein: The first stroke includes a pumping stroke phase and a first conversion phase occurring in a transition from the first stroke to the second stroke; The first conversion phase forms the last fifteen percent of the length of the first stroke; and The second stroke includes a suction stroke phase and a second conversion phase occurring in a transition from the second stroke to the first stroke.

52. A pump according to any one of claims 42 to 48, wherein: The first stroke includes a pumping stroke phase and a first conversion phase occurring in a transition from the first stroke to the second stroke; The first conversion phase forms the last ten percent of the length of the first stroke; and The second stroke includes a suction stroke phase and a second conversion phase occurring in a transition from the second stroke to the first stroke.

53. A pump according to any one of claims 42 to 48, wherein: The first stroke includes a pumping stroke phase and a first conversion phase occurring in a transition from the first stroke to the second stroke; The first conversion phase forms the last five percent of the length of the first stroke; and The second stroke includes a suction stroke phase and a second conversion phase occurring in a transition from the second stroke to the first stroke.

54. A pump according to any one of claims 42 to 53, wherein The controller is configured to exit the starting mode and enter the pumping mode based on an amount of current draw by the electric motor.

55. A pump according to any one of claims 42 to 54, wherein The controller is configured to exit the start-up mode and enter the pumping mode based on a first time threshold.

56. A pump according to claim 55, wherein The controller is configured to re-enter the start-up mode from the pumping mode based on a second time threshold after first having exited the start-up mode.

57. A pump according to claim 56, wherein The first time threshold is an upper limit, and the second time threshold is a lower limit.

58. A pump according to any one of claims 55 to 57, wherein The controller is configured to re-enter the start-up mode from the pumping mode after first having exited the start-up mode based on a threshold value of a sensed parameter of the electric motor.

59. A pump according to claim 58, wherein The sensed parameter of the electric motor is the current draw of the electric motor.

60. A pump according to any one of claims 42 to 53, wherein The controller is configured to automatically enter the start mode based on an amount of current draw by the electric motor.

61. A pump according to claim 60, wherein The controller is configured to automatically enter the startup mode based on the current draw being less than a current threshold.

62. A pump according to any one of claims 42 to 61, wherein The controller is configured to regulate the energy delivery to the electric motor such that a pumping acceleration profile of the first fluid displacer during the pumping mode is different than a start-up acceleration profile of the first fluid displacer during the start-up mode.

63. A pump according to any one of claims 42 to 62, wherein The controller is configured to regulate the energy delivery to the electric motor such that a pumping deceleration profile of the first fluid displacer during the pumping mode is different than a startup deceleration profile of the first fluid displacer during the startup mode.

64. The pump of claim 42, wherein: The controller is configured to regulate the energy delivery to the electric motor such that: During the start-up mode, the first fluid displacer moves a first distance through the first stroke, a maximum speed of the first fluid displacer is based on a first speed set point, and the first fluid displacer pauses during transitions for a first period of time; During the pumping mode, the first fluid displacer moves a second distance through the first stroke, a maximum speed of the first fluid displacer is based on a second speed set point, and the first fluid displacer pauses for a second period of time during transitions; and The first distance is different from the second distance, the first speed set point is different from the second speed set point, and the first time period is different from the second time period.

65. A pump according to claim 64, wherein The first distance is greater than the second distance.

66. A pump according to any one of claims 64 and 65, wherein The first speed set point is greater than the second speed set point.

67. A pump according to any one of claims 64 to 66, wherein The first time period is longer than the second time period.

68. A pump according to any one of claims 42 to 67, wherein The controller is configured to regulate the energy delivery to the electric motor based on a current threshold, and wherein the current threshold is based on an input voltage and a target speed.

69. A pump according to claim 68, wherein The current threshold is also based on the motor temperature.

70. The pump of claim 69, wherein The current threshold is recalled from a three-dimensional table stored in a memory of the controller.

71. A pump for pumping a fluid, the pump comprising: a first fluid chamber; a first inlet check valve and a first outlet check valve, the first inlet check valve and the first outlet check valve being positioned upstream and downstream of the first fluid chamber, respectively, and regulating flow into and out of the first fluid chamber; an electric motor including a stator and a rotor configured to generate a rotational output; a driver that converts the rotational output from the electric motor into linear reciprocating motion; a first fluid displacer configured to be driven by the driver to perform linear reciprocating motion along the axis and at least partially within the first fluid chamber to pump the fluid, wherein the first fluid displacer reciprocates through a series of consecutive pump cycles, each pump cycle comprising: a first stroke along the axis in a first direction, a second stroke along the axis in a second direction, a first transition of the first fluid displacer to reverse direction from the first stroke to the second stroke, and a second transition of the first fluid displacer to reverse direction from the second stroke to the first stroke; and a controller configured to regulate energy delivery to the electric motor in a startup mode in which the pump is activated and in a pumping mode, wherein the controller regulates the energy delivery so that the first fluid displacer moves a first distance through the first stroke in the startup mode and the fluid displacer moves a second distance through the first stroke in the pumping mode, the first distance being greater than the second distance.

72. A pump for pumping a fluid, the pump comprising: a first fluid chamber; a first inlet check valve and a first outlet check valve, the first inlet check valve and the first outlet check valve being positioned upstream and downstream of the first fluid chamber, respectively, and regulating flow into and out of the first fluid chamber; an electric motor including a stator and a rotor configured to generate a rotational output; a driver that converts the rotational output from the electric motor into linear reciprocating motion; a first fluid displacer configured to be driven by the driver at least partially to perform linear reciprocating motion within the first fluid chamber to pump the fluid, wherein the first fluid displacer reciprocates through a series of consecutive pump cycles, each pump cycle comprising a pumping stroke phase, a suction stroke phase, and a conversion phase, the conversion phase occurring at each transition between the pumping stroke phase and the suction stroke phase, during which the first fluid displacer reverses direction; and a controller configured to regulate energy delivery to the electric motor in a starting mode in which the pump is activated and in a pumping mode, and wherein the controller regulates the energy delivery in the starting mode so that the rotor rotates to cause the first fluid displacer to cause a transition phase during the starting mode to be slower than a transition phase during the pumping mode.

73. A pump for pumping a fluid, the pump comprising: a first fluid chamber; a first inlet check valve and a first outlet check valve, the first inlet check valve and the first outlet check valve being positioned upstream and downstream of the first fluid chamber, respectively, and regulating flow into and out of the first fluid chamber; an electric motor including a stator and a rotor configured to generate a rotational output; a driver that converts the rotational output from the electric motor into linear reciprocating motion; a first fluid displacer configured to be driven by the driver at least partially to perform linear reciprocating motion within the first fluid chamber to pump the fluid, wherein the first fluid displacer reciprocates through a series of consecutive pump cycles, each pump cycle comprising a pumping stroke phase, a suction stroke phase, and a conversion phase, the conversion phase occurring at each transition between the pumping stroke phase and the suction stroke phase, during which the first fluid displacer reverses direction; and A controller configured to regulate energy delivery to the electric motor in a startup mode in which the pump is activated and in a pumping mode, and wherein the controller regulates the energy delivery in the startup mode so that the first fluid displacer pauses for a first time period during a transition phase during the startup mode and pauses for a second time period during a transition phase in the pumping mode, the first time period being longer than the second time period.

74. A diaphragm for a pump configured to reciprocate along an axis to pump a fluid, the diaphragm comprising: a first diaphragm plate; and a flexible body extending radially outward from the diaphragm plate, the flexible body having an outer side and an inner side, the outer side being oriented in a first direction along the axis and being configured to be oriented toward a pumping chamber through which the fluid is pumped, and the inner side being oriented in a second direction along the axis and being configured to be oriented toward a motor that drives reciprocating motion of the diaphragm, the flexible body comprising: - a main diaphragm comprising a flange enlarged relative to a diaphragm body of the main diaphragm, the flange being configured to be clamped to mount the diaphragm to the pump; and - a backing formed separately from the main diaphragm and arranged such that the main diaphragm is located between the backing and the outer side of the flexible body, the backing comprising a flange cup open in the first direction and configured to receive the flange.

75. The diaphragm of claim 74, wherein: In an unflexed state, the backing includes a central portion, a groove radially outward from the central portion, and the flange cup radially outward of the groove.

76. The diaphragm of claim 75, wherein: The groove is annular and open in the second direction.

77. The membrane of any one of claims 74 to 76, wherein: The membrane body has a first thickness, the backing body of the backing has a second thickness, and the first thickness is greater than the second thickness.

78. The membrane of any one of claims 74 to 77, wherein The primary membrane is formed from a first polymer and the backing is formed from a second polymer.

79. The diaphragm of claim 78, wherein: The first polymer is different from the second polymer.

80. The diaphragm according to any one of claims 78 and 79, wherein The second polymer is a thermoplastic vulcanizate (TPV).

81. The membrane of any one of claims 78 to 80, wherein The second polymer includes fully cured ethylene propylene diene monomer (EPDM) rubber particles encapsulated in a polypropylene matrix.

82. The diaphragm according to any one of claims 78 and 79, wherein The second polymer is polytetrafluoroethylene (PTFE).

83. The diaphragm of any one of claims 74 to 82, wherein: The main diaphragm is exposed on the outer side of the flexible body.

84. The diaphragm of any one of claims 74 to 83, wherein The backing is exposed at the inner side of the flexible body.

85. The diaphragm of any one of claims 74 to 84, further comprising: A second diaphragm plate, wherein the primary diaphragm and the backing are sandwiched between the first diaphragm plate and the second diaphragm plate.

86. The diaphragm of claim 85, wherein: The primary diaphragm is overmolded onto the first diaphragm plate.

87. The diaphragm of any one of claims 74 to 86, wherein The backing is not adhered to the primary membrane.

88. The diaphragm of any one of claims 74 to 87, wherein The flexible body does not include an adhesive securing the backing to the main diaphragm.

89. A pump for pumping a fluid, the pump comprising: a pump body at least partially defining a motor housing; an electric motor disposed within the motor housing and configured to generate a rotational output; a driver that converts the rotational output from the electric motor into linear reciprocating motion along an axis; a first fluid chamber at least partially defined by a first fluid cover connected to the pump body; and A first diaphragm, the first diaphragm is configured to be driven by the driver to at least partially perform linear reciprocating motion along the axis within the first fluid chamber to pump the fluid through the first fluid chamber, the first diaphragm comprising: a first diaphragm plate; and a flexible body extending radially outward from the diaphragm plate and at least partially defining the first fluid chamber, the flexible body having an outer side oriented toward the first fluid chamber and an inner side oriented toward the electric motor, the flexible body comprising: a primary diaphragm including a flange that is enlarged relative to a diaphragm body of the primary diaphragm; and a backing formed separately from the main diaphragm and arranged such that the backing is located between the main diaphragm and the electric motor, the backing including a flange cup configured to receive the flange, the flange cup opening in a direction axially away from the electric motor; The flange and the flange cup are clamped between the first fluid cover and the pump body.

90. The pump of claim 89, wherein The backing is not secured to the primary membrane.

91. A pump according to any one of claims 89 and 90, wherein The fluid cover includes a first annular groove, the pump body includes a second annular groove opposite to the first annular groove, and the flange and the flange cup are arranged in a mounting groove formed by the first annular groove and the second annular groove.

92. A pump according to any one of claims 89 to 91, wherein The primary membrane is formed from a first polymer and the backing is formed from a second polymer.

93. The pump of claim 92, wherein: The first polymer is different from the second polymer.

94. A pump according to any one of claims 92 and 93, wherein The second polymer is a thermoplastic vulcanizate (TPV).

95. A pump according to any one of claims 92 to 94, wherein The second polymer includes fully cured ethylene propylene diene monomer (EPDM) rubber particles encapsulated in a polypropylene matrix.

96. A pump according to any one of claims 92 and 93, wherein The second polymer is polytetrafluoroethylene (PTFE).

97. A pump according to any one of claims 89 to 96, wherein The primary diaphragm is exposed to the first fluid chamber such that the primary diaphragm contacts the fluid during pumping.

98. A pump according to any one of claims 89 to 97, wherein The diaphragm body of the main diaphragm has a first thickness, the backing body of the backing has a second thickness, and the first thickness is greater than the second thickness.

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