Reciprocating piston pump and method for controlling a reciprocating piston pump

Abstract

The invention relates to a reciprocating piston pump (1, 1') having a fluid-conducting pump housing (2) and a pump axis (10), and a fluid-conducting, axially movable pump piston (19) which is arranged coaxially to two ring coils, namely a first ring coil (12') and a second ring coil (12''), which are fixed to the housing, wherein the reciprocating piston pump (1) has two inlet valves, namely a first inlet valve (20') and a second inlet valve (20''), and two outlet valves, namely a first outlet valve (21') and a second outlet valve (21''), wherein the first inlet valve (20') and the first outlet valve (21') are arranged concentrically to the pump axis (10) in the first ring coil (12'), and the second inlet valve (20') and the second outlet valve (21') are arranged concentrically to the pump axis (10) in the second ring coil (12''), and the pump piston (19) is guided in a two-part guide sleeve or directly in the pump housing (2) in a two-part working chamber.

Description

Technical Field

[0001] The present invention relates to a reciprocating piston pump having a pump housing through which fluid flows and a pump piston that is axially movable and through which fluid flows, and is coaxially arranged with two annular coils fixed to the housing.

[0002] The present invention also includes a method for controlling a reciprocating piston pump. Background Technology

[0003] In electric traction drive systems, oil pumps driven by brushless DC motors (BLDC motors) are typically used. These pumps provide a delivery volumetric flow rate that can be set on demand via speed regulation of the BLDC motor, independent of vehicle speed. As a preferred pump type, rotary positive displacement pumps, also known as ring gear pumps or cycloidal rotor pumps, are used in implementations. These pumps consist of a gear set with an inner and outer rotor and a pump housing typically composed of two or three parts. Nevertheless, this inherently simple and proven implementation still incurs high costs for the motor-pump unit, especially for the BLDC motor and the commutation electronics required for motor control, such as BLDC drives or B6 bridge circuits. If the commutation electronics are not directly integrated into the motor but rather into the central transmission control unit or the inverter control board of the electric traction machine, additional costs arise for the consumable wiring harnesses and connectors.

[0004] Although the more cost-effective implementation scheme than brushed DC motors can be operated in a simple manner, it cannot operate without wear due to sliding contacts, resulting in a significantly shortened service life.

[0005] For example, a mechanically driven oil pump via the transmission intermediate shaft has the following disadvantages: the achievable volumetric flow rate depends on the vehicle speed. Therefore, in certain operating conditions, such as high torque and low vehicle speed, insufficient cooling oil flow cannot be provided. Furthermore, in secondary drive units without a mechanically disengaging clutch, drag power is continuously generated.

[0006] In particular, for applications in electric assisted drive, the required active operating time percentage and overall cooling oil demand are very low throughout the vehicle's lifespan compared to the primary application. Therefore, considering cost and efficiency requirements, the above-described implementation schemes known from the prior art are not entirely satisfactory solutions.

[0007] In addition, electromagnetically actuated vibratory piston pumps or diaphragm pumps are already used in other automotive applications. These are typically designed in-line configurations for direct-access piping, providing only very small delivery volumetric flow rates. They serve as metering pumps for parking heaters and auxiliary heaters, as AdBlue metering pumps, or as fuel metering pumps for exhaust thermal management. However, in these applications, compared to eDrive oil used in electric drives, the delivered medium is significantly lower viscosity, such as diesel or AdBlue. Vibratory piston pumps or diaphragm pumps used as metering pumps are typically designed for very small delivery volumetric flow rates, often resulting in audible operation.

[0008] In cooling water circulation, impeller pumps or centrifugal pumps are also used as circulating pumps. These turbine pumps, which operate based on fluid dynamics principles, require electric drive and, unlike the positive displacement pumps mentioned above, cannot self-prime without additional measures.

[0009] The object of this invention is to provide an improved pump comprising a cost-optimized and function-optimized electromagnetically operable reciprocating piston pump having a double-acting, double-sided loaded pump piston and an optional valve for controlling a portion of the volumetric flow according to oil temperature. Summary of the Invention

[0010] The objective is achieved by a reciprocating piston pump having a fluid-flowing pump housing and a fluid-flowing pump piston that is axially movable and coaxially arranged with two annular coils fixed to the housing, wherein an inlet valve and an outlet valve are arranged concentrically with the pump axis and radially inside the annular coils, and the pump piston is guided in a two-piece volumetric cavity by a two-piece guide sleeve or a yoke directly disposed in the pump housing.

[0011] The pump piston integrates the functions of a movable armature (the armature of the magnetic circuit) and a delivery piston.

[0012] The pump piston can move in a double-acting manner in the axial direction of a reciprocating piston pump.

[0013] Preferably, the pump piston is made of a material with good magnetic permeability and high relative permeability, wherein the material is preferably iron (Fe), iron-silicon (FeSi), or free-cutting steel (11SMn30).

[0014] Furthermore advantageously, the first and second bearing bushings are made of a material with good magnetic permeability and high relative permeability, wherein the material is preferably iron (Fe), iron-silicon (FeSi), or free-cutting steel (11SMn30).

[0015] In a further advantageous embodiment, the bearing bushing is thick-walled with a wall thickness of 1 mm to 3 mm.

[0016] In one improved embodiment, the two-piece guide sleeve includes a first bearing bushing and a second bearing bushing, wherein the first and second bearing bushings are made of magnetically insulated material having a low relative permeability (µm). r ~ 1) The material implementation, wherein the preferred material is aluminum (Al), (EN AW 6062), stainless steel or brass.

[0017] In a further embodiment, the pump piston has a magnetically insulating coating, preferably a Teflon or chromium nitride coating, on its outer surface, or the first and second bearing bushings have a coating on their inner surfaces, wherein the coating advantageously has a layer thickness of 20 µm to 100 µm. Particularly advantageously, the chromium nitride layer thickness is on the order of 20 µm to 25 µm, and the PTFE layer thickness is on the order of 25 µm to 50 µm. The coating must be magnetically insulating, have high wear resistance, and good sliding properties / low frictional resistance.

[0018] In embodiments where the guide bushing is configured as an alternative to the bearing bushing, these configurations are metal-polymer sliding bearing bushings consisting of a magnetically conductive steel backing and a magnetically insulated sliding bearing layer.

[0019] By constructing the pump piston with a magnetically insulating cladding, the pump piston can be guided directly within the yoke disks, i.e., within the first and second yoke disks. During axial movement of the pump piston, the pump piston slides on the inner surfaces of the first and second yoke disks by means of its outer surface or the cladding. Alternatively, the inner surfaces of the yoke disks may include the cladding.

[0020] A coating with good sliding properties and high wear resistance is, for example, a thin-walled Teflon layer. Thus, the pump piston can be directly guided within a coil body made of, for example, PPS + 50 GF / MD plastic or on an electrode plate made of, for example, 11SMnPb30 steel. Cost-intensive, thin-walled, magnetically insulated stainless steel or brass sleeves can be eliminated.

[0021] By using two short guide bushings instead of a continuous thin-walled guide sleeve, the two guide bushings, namely the first and second guide bushings, can also be implemented with a larger wall thickness (1 mm to 3 mm), which makes manufacturing simpler and more cost-effective.

[0022] In the previously described embodiments, the basic idea is to coat the components, which move relative to each other and function as magnetic flux guiding elements, with a magnetically insulating coating. Here, the magnetically insulating coating simultaneously functions to improve wear and friction characteristics and minimize magnetic losses.

[0023] The same principle can be achieved by using a metal-polymer sliding bearing bushing, which consists of a magnetically conductive steel back and a magnetically insulated sliding bearing layer.

[0024] In a further preferred embodiment, the valve is flanged to the reciprocating piston pump on the output side and provides two passages. By using the valve to control a portion of the volumetric flow on demand, such as to the stator and rotor of a wet-running oil-cooled motor, the required pump size can be significantly reduced compared to a fixed distribution of the volumetric flow. The energy demand of the pump during operation is also reduced. Due to the pulsation of the delivery flow caused by the principle and the resulting pressure pulsation, pressure-controlled valves cannot be used advantageously. Therefore, a temperature-controlled valve is proposed, which is controlled via a temperature-sensitive element, such as a temperature-sensitive spring or wax pack.

[0025] The described embodiment features an outwardly open pump housing. The coolant / lubricant pump, disposed within a fluid bottom casing, exhibits targeted guidance of fluid flow on both the inlet and outlet sides to maximize convective heat dissipation through the operating medium.

[0026] The fixed inlet valve to the housing and the guidance via the pressure side of the axially movable pump piston offer functional advantages. This avoids the risk of air release in the suction path—since there is no need for multiple turns at sharp edges—and limits the risk of throttling at higher reciprocating frequencies.

[0027] The objective is also achieved by a method for controlling a reciprocating piston pump, wherein the control of the pump piston is performed via a current curve having positive and negative current pulses.

[0028] An improved version of the inventive concept proposes to provide hydraulic end-position damping through a stroke-controlled orifice plate geometry at the pump piston.

[0029] Advantageously, electromagnetic damping is achieved by adjusting the current curve of the coil.

[0030] Furthermore, short-term overload operation is feasible.

[0031] An improved embodiment of the method according to the invention proposes that the transport flow be actively distributed via a temperature-sensitive element.

[0032] A preferred improvement to this method is the use of a coil heating device to improve low-temperature start-up performance.

[0033] Instead of rotary positive displacement pumps known from the prior art, a cost-effective oscillating positive displacement pump is used. An electromagnetic linear actuator, controlled by a corresponding current curve, operates a double-stroke piston to displace fluid. The delivery volume flow is controlled by the frequency and amplitude of the current curve. Attached Figure Description

[0034] Figure 1 A hydraulic circuit diagram of an electromagnetically operable reciprocating piston pump according to the present invention is shown.

[0035] Figure 2 An isometric view of a first embodiment of an electromagnetically operable reciprocating piston pump according to the present invention is shown.

[0036] Figure 3 Shown in Figure 2 The image shows an end view of a reciprocating piston pump.

[0037] Figure 4 Shown in Figure 2 and Figure 3 The first sectional view of the reciprocating piston pump shown in the figure is along the section plane AA.

[0038] Figure 5 Shown in Figure 2 and Figure 3 The second sectional view of the reciprocating piston pump shown in the figure is along the section plane BB.

[0039] Figure 6 Shown in Figures 2 to 5 The image shows a detailed sectional view along section plane BB of a reciprocating piston pump with an integrated pump piston and valve electromagnetic actuator.

[0040] Figure 7 An isometric view of another embodiment of the electromagnetically operable reciprocating piston pump according to the invention, having an integrated valve for on-demand control of partial volumetric flow.

[0041] Figure 8 Shown in Figure 7 The image shows an end-side view of a reciprocating piston pump with an integrated valve for on-demand control of partial volumetric flow.

[0042] Figure 9 Shown in Figure 7 The image shows a cross-sectional view of a reciprocating piston pump along section plane AA.

[0043] Figure 10 Shown in Figure 7 The image shows a cross-sectional view of a reciprocating piston pump along section plane BB.

[0044] Figure 11 A cross-sectional view along the section plane CC is shown.

[0045] Figure 12 A cross-sectional view along the section plane DD is shown.

[0046] Figure 13 Showing according to Figures 2 to 11An isometric view of a dual-coil assembly (not shown) of an annular coil winding in an electromagnetically operable reciprocating piston pump according to the present invention.

[0047] Figure 14 Shown in Figure 13 The image shows an end-side view of the dual-coil assembly.

[0048] Figure 15 Shown in Figure 13 The image shows a cross-sectional view of the dual-coil assembly along the section plane EE.

[0049] Figure 16 An isometric view of the yoke is shown.

[0050] Figure 17 A schematic embodiment is shown for connecting two electromagnetic coils of a dual-coil pump according to the invention.

[0051] Figure 18 Another illustrative embodiment for connecting the two electromagnetic coils of the dual-coil pump according to the invention is shown.

[0052] Figure 19a and Figure 19b An exemplary current profile is shown for electrically controlling an electromagnetically operable dual-coil pump according to the present invention.

[0053] Figure 20 Shown in Figure 8 A first cross-sectional view along section plane AA of another embodiment of an electromagnetically operable reciprocating piston pump according to the invention, having two single-coil assemblies.

[0054] Figure 21 Shown in Figure 8 A second cross-sectional view of an electromagnetically operable reciprocating piston pump according to the invention, having two single-coil assemblies, along the cross-sectional plane BB.

[0055] Figure 22 An isometric view of a coil body with an integrated yoke is shown.

[0056] Figure 23 An end-side view of the coil body with an integrated yoke is shown (in...) Figure 22 View A in the middle.

[0057] Figure 24 Shown in Figure 20 and Figure 21 An isometric view of the assembly of a single coil assembly in an embodiment of a reciprocating piston pump is shown.

[0058] Figure 25 An end-side view of the assembled single-coil assembly is shown (in...) Figure 24 View A in the middle.

[0059] Figure 26 Shown in Figure 22 and Figure 23 The coil body shown in the figure, with an integrated yoke, runs along the... Figure 23 The sectional view of the section plane FF in the diagram.

[0060] Figure 27 Shown in Figure 24 and Figure 25 The assembly of the single coil assembly shown in the figure follows the direction of... Figure 25 The sectional view of the section plane GG in the diagram.

[0061] Figure 28 A detailed view of another embodiment is shown in the area between the yoke and the pump piston.

[0062] Figure 29 A detailed view of the first embodiment is shown in the area between the two-piece guide sleeve and the pump piston. Detailed Implementation

[0063] Figure 1 A hydraulic circuit diagram of an electromagnetically operable reciprocating piston pump 1 is shown, the reciprocating piston pump having a suction side 7 and a pressure side 8. The pump piston 19 is operated via a first coil implemented as a ring coil 12' and a second coil implemented as a ring coil 12''.

[0064] exist Figure 17 and Figure 18 A feasible electrical connection between the first ring coil 12' and the second ring coil 12'' is shown. Figure 19a and 19b An exemplary current curve for controlling the reciprocating piston pump 1 is shown in the figure.

[0065] In this embodiment, the dual-loaded pump piston 19 is manipulated in two directions by alternating electromagnetic forces via a dual-coil stroke electromagnet.

[0066] Figures 2 to 6 A first embodiment of an electromagnetically operable reciprocating piston pump 1 according to the present invention is shown. The reciprocating piston pump 1 has a pump axis 10. In the context of the present invention, axial direction refers to the direction along the pump axis 10.

[0067] Figure 2 An isometric view of a reciprocating piston pump 1 is shown, the pump having a pump housing 2 and a pump cover 3. A plug 4 is installed on the pump cover 3.

[0068] The pump housing 2 has a plurality of housing webs 29 on its outer circumference. The pump housing 2 with the housing webs 29 is housed within and centrally held in a housing cavity (not shown) of the transmission housing. The pump housing 2 has channels extending parallel to each other, which form flow channels on the inlet and outlet sides. The pump inlet 5 is located on the suction side 7, while the pump outlet 6 is located on the pressure side 8.

[0069] The inlet channel is formed between the pump housing 2 and the housing web 29, while the outlet channel 9 is closed radially outward toward the pump housing 2. This ensures that the annular coils 12', 12'' installed in the pump housing 2 effectively dissipate heat from the outside through the fluid flowing around them. The defined flow around the annular coils 12', 12'' is feasible by correspondingly designing the housing web 29.

[0070] There is a pump housing 2 through which oil flows, the pump housing having a wet-operated stroke electromagnet and an oil-damped movement of the pump piston.

[0071] In addition to the axial flow shown, other embodiments are conceivable, such as spiral or meandering flow patterns. Thus, good heat dissipation can be ensured through convection, and additional functions, such as coil heating for low-temperature operation or sufficiently accurate fluid temperature measurement via resistance measurements on the coil windings, can be achieved.

[0072] Furthermore, for the housing components, plastic injection molded parts, for example, made of PPS + 50% GF, can be used, thereby enabling a cost-effective pump design.

[0073] The first and second outlet channels 9' and 9'' converge in the pump outlet 6. The fluid volume located in the region of the pump outlet 6 on the pressure side 8 acts as a damping volume to smooth out pulsations in the transport flow caused by the principle.

[0074] On the inlet side, fluid is guided to the first and second inlet valves 20', 20'' of the reciprocating piston pump 1 via axially and radially introduced cavities located on the suction side 7. These cavities serve as pump inlets 5 within the pump housing 2. (The text abruptly ends here, so the translation stops as well.) Figure 4 , Figure 5 , Figure 6 , Figure 9 and Figure 10 As can be seen in the cross-sectional view, when viewed in the axial direction of the reciprocating piston pump 1, the first inlet valve 20' is located on the left side of the pump piston 19, while the second inlet valve 20'' is located on the right side of the pump piston 19. This achieves a double-acting working principle with a pump piston that is loaded on both sides, and enables convection cooling of the pump's electromagnetic active components via the working medium on both the suction and pressure sides, and radially internally and radially externally.

[0075] The electromagnetic active components of the reciprocating piston pump 1 include: two pole cores, two pole discs, two housings, two yoke discs, and two annular coils. The arrangement of these components is described in detail below with reference to the sectional view. The electromagnetic active components are fixed to the housing and enclosed by the partially open pump housing 2. This ensures good heat dissipation through the surrounding fluid.

[0076] Additionally, this can be supported by the use of a guiding device that directs fluid radially and axially around the outer surface of the pump housing 2 and subsequently to the first and second inlet valves 20', 20''. The guiding device can be configured as a single, one-piece, or multi-piece insert, or implemented through a special design of the housing web 29. That is, the housing web 29 need not be forced to extend parallel to the pump axis 10, but can be implemented such that a meandering or threaded flow channel is formed between the pump housing 2 with the housing web 29 and the receiving cavity in the transmission housing.

[0077] Figure 3 A top view of pump housing 2 is shown (in...) Figure 2 View A in the middle.

[0078] Figure 4 A longitudinal section is shown through the electromagnetically operable reciprocating piston pump 1 according to the invention, i.e., in Figure 3 The cross-sectional plane AA in the middle.

[0079] The reciprocating piston pump 1 is implemented with a dual-coil assembly 25, and has two annular coils fixed to the housing, namely first and second annular coils 12', 12'', which are disposed on a common coil body 11. Other soft magnetic components (active electromagnetic components) required for the corresponding electromagnetic circuit, namely the pole core, pole disc, housing, and yoke, are similarly implemented for the first and second annular coils 12', 12'' and are positioned relative to the coil body 11 and the axis SA ( Figure 9 It is set symmetrically along the axis.

[0080] Therefore, the first ring coil 12' is equipped with a first pole core 14', a first pole disk 15', a first outer shell 16', and a first yoke disk 17'. The second ring coil 12'' is equipped with a second pole core 14'', a second pole disk 15'', a second outer shell 16'', and a second yoke disk 17''.

[0081] Figure 5 Another longitudinal section is shown passing through the reciprocating piston pump 1 along the pump axis 10, i.e., in Figure 3The cross-section BB is shown in the diagram. The arrows symbolize the flow path through the suction and pressure sides of the reciprocating piston pump 1. Fluid is drawn in through two inlet valves, namely the first inlet valve 20' and the second inlet valve 20''. The arrows indicate the fluid inflow to the suction side 7. The fluid flows into the pump chamber, more specifically into the first working chamber 24' and the second working chamber 24'', via the first outlet valve 21' and the second outlet valve 21'' and through the coil body 11. On the pressure side, the fluid flows through the first outlet channel 9' and the second outlet channel 9'' to the pump outlet 6 on the pressure side 8.

[0082] Figure 6 Shown in Figure 5 The figure shows a detailed sectional view of longitudinal section BB. In the figure, the pump piston 19 moves to the right in the axial direction, and the volume of the second working chamber 24'' decreases, and thus the fluid located therein is compressed ("top dead center"). Conversely, the first working chamber 24'' shows its maximum capacity ("bottom dead center").

[0083] The pump piston 19 is guided via a two-piece guide sleeve, which consists of two short bearing bushings, namely a first bearing bushing 23' and a second bearing bushing 23'' made of bearing bronze or other sliding bearing material. This split bearing bushing configuration, and the division into first and second bearing bushings 23', 23'', eliminates the need for a continuous, thin-walled guide sleeve. Furthermore, the two bearing bushings, namely the first bearing bushing 23' and the second bearing bushing 23'', can be implemented with a greater wall thickness, for example, in the range of 1.5 mm to 3 mm. The radial clearance S required for magnetic insulation between the first yoke 17' or the second yoke 17'' and the pump piston 19, due to functional requirements, can still be kept small (the diameter clearance is preferably in the range of 0.03 mm to 0.06 mm), which has a favorable effect on the magnetic circuit. Cost-intensive thin-walled stainless steel sleeves can be eliminated. These are typically drawn stainless steel or brass tubes with the smallest possible wall thickness to minimize electromagnetic losses, usually less than 0.4 mm, ideally 0.2 mm.

[0084] Figures 7 to 10 Another embodiment of an electromagnetically operable reciprocating piston pump 1 according to the present invention is shown, the reciprocating piston pump having a function for controlling two partial volumetric flows, namely a first partial volumetric flow Q. A Second part volume flow Q B The integrated valve 30. A specific embodiment of the reciprocating piston pump 1 can optionally utilize valve 30. All other components remain as is and are already in place. Figures 2 to 6 As described in the text.

[0085] Valve 30 has a valve body 31 and a valve cover 32.

[0086] Figure 8 The valve 30 is shown in an end-side view on the reciprocating piston pump 1.

[0087] Figure 9 The structure of valve 30 is shown in cross-sectional view along pump axis 10. Viewed radially, a cylindrical valve piston 33 is disposed within valve housing 31. A first valve spring 34 is located on the outer surface of valve piston 33 between valve housing 31 and valve piston. The valve spring is helically formed. The first valve spring 34 is a temperature-sensitive spring. Alternatively, a wax element can be used. A second valve spring 35, serving as the return spring of valve 30, is located within valve piston 33. A first outlet 36 is located radially on a flange, through which valve 30 is connected to pump housing 2. A second outlet 37 is axially parallel to pump axis 10 and disposed on the end side of valve housing 31.

[0088] Figure 10 The reciprocating piston pump is shown in a view rotating about its pump axis 10, such that the first outlet 36 is visible in the top view of the accompanying drawing.

[0089] exist Figure 11 Select along in Figure 9 The cross-section of the midplane CC is shown, precisely centered along the axis SA between the first annular coil 12' and the second annular coil 12''. The housing web 29 is visible, also including a first outlet channel 9' and a second outlet channel 9''. The pump piston 19 is visible, located radially inward of the coil body 11. The first and second annular coils 12', 12'' are contacted via a first slot 28' and a second slot 28'' for wire threading.

[0090] exist Figure 12 The cross-section of the valve seat approximately along the first outlet valve 21' is visible. The first annular coil 12' can be seen located radially outside the first bearing bushing 23'. The pump piston 19 and the first outlet valve 21' are disposed within the first bearing bushing 23'.

[0091] Figures 13 to 15 Different views of the dual-coil assembly 25 are shown, which consists of a common coil body 11 and integrated yokes, namely a first yoke 17' and a second yoke 17''. The windings of the two toroidal coils 12', 12'' on the coil body are not shown here.

[0092] Preferably, the dual-coil assembly 25 is implemented as a plastic injection-molded component having first and second yoke discs 17', 17'' encapsulated in an injection mold. Here, the first and second yoke discs 17', 17'' are inserted into the injection mold as inserts and encapsulated with the coil body 11 in an injection mold. The annular groove 27, which is centrally located, is functionally required for the guidance of oil and wires; the groove has a first empty portion 26' and a second empty portion 26'' for the pump outlet; and the groove has a first groove 28' and a second groove 28'' for wire threading. Therefore, it can be cost-effectively integrated into the plastic injection-molded component.

[0093] Figure 15 The dual-coil assembly 25, as a plastic injection-molded component, is shown in cross-section. The dual-coil assembly has two injection-molded encapsulated yokes, namely a first yoke 17' and a second yoke 17'', and an annular groove 27 that is centrally and radially surrounded.

[0094] Figure 16 An isometric view of an exemplary embodiment of a first yoke 17' is shown, the first yoke having integrated grooves 28', 28'' and a through-hole 38 required for injection molding encapsulation. For cost reasons, the yoke is preferably manufactured as a deep-drawn / pressed part with a calibrated inner diameter. The through-hole 38 is implemented as an axially extending hole.

[0095] Figure 17 A schematic diagram is shown for connecting two electromagnetic coils, namely a first annular coil 12' and a second annular coil 12'', to the reciprocating piston pump 1 according to the present invention. A two-pole electrical interface 40 is connected to the first coil 12' and the second coil 12'' via a first freewheeling diode 39' and a second freewheeling diode 39'', respectively.

[0096] Figure 18 Another schematic diagram is shown for connecting the first toroidal coil 12' and the second toroidal coil 12''. The first toroidal coil 12' and the second toroidal coil 12'' are voltage-loaded via a three-pole interface 41.

[0097] Figure 19a and Figure 19b Two different methods for controlling a pump are illustrated, differing in particular in the achievable dynamics (maximum reciprocating frequency) and electrical power consumption (energy efficiency).

[0098] The coordinate system shown is a current i / time t graph. The current curve is indicated by a period T 43 and positive half-wave 44' and negative half-wave 44'' in sinusoidal or step shape.

[0099] exist Figure 19a The current curve 44' is depicted as a sinusoidal extension. Figure 19bThe figure depicts a stepped curve 45' with multiple current levels i1, i2, i3.

[0100] The two control methods differ, particularly in the achievable reciprocating frequency and energy efficiency (the electrical energy consumed by the coil corresponds to the shaded area).

[0101] Figures 20 to 27 Another embodiment of the design of the reciprocating piston pump 1' according to the present invention is shown. The difference between this embodiment and the previously described embodiment is that instead of a common coil body 11 and the first and second annular coils 12' and 12'' forming a double coil assembly 25, two single coil assemblies 25' are implemented, which are housed in the pump housing 2.

[0102] for Figures 20 to 27 This description focuses solely on the differences between the previously described embodiment of the reciprocating piston pump 1 according to the invention and the one described herein. Identical components are represented by the same reference numerals.

[0103] Figure 20 and Figure 21 Another embodiment of the reciprocating piston pump 1' according to the invention is shown in two different longitudinal sections (rotated 90 degrees).

[0104] The reciprocating piston pump 1' is implemented with two single-coil assemblies 25'. Each of the two single-coil assemblies has a ring coil, namely a first ring coil 12' and a second ring coil 12'', which are each individually mounted on a coil body. That is, the first ring coil 12' is mounted on the first coil body 11' and the second ring coil 12'' is mounted on the second coil body 11''. Other soft magnetic components (active electromagnetic components) required for the corresponding electromagnetic circuit, namely the pole core, pole plate, housing, and yoke, are implemented identically for the first and second ring coils 12', 12''.

[0105] exist Figure 20 and Figure 21 The two single-coil assemblies 25' are preferably constructed symmetrically (identical components). For simplicity, the following is based on... Figures 22 to 27 Only one of the two single-coil assemblies 25' is shown and described.

[0106] exist Figure 24 , Figure 25 , Figure 27 The two pre-assembled single-coil assemblies 25' shown are symmetrically mounted in the reciprocating piston pump 1' according to the invention, thereby enabling cost-effective manufacturing. Additional components, such as spacer rings for positioning the coil assemblies, can be eliminated.

[0107] Figure 22An isometric view of a first coil body 11' is shown, the first coil body having an integrated first yoke 17'. The first coil body 11' is preferably implemented as a plastic injection-molded component. Not only can the first yoke 17' be implemented as an insert and injection-molded together with the first coil body 11' during the injection molding process, but a multi-piece implementation of the coil body and yoke is also feasible.

[0108] Figure 22 The configuration of radially extending empty portions 26' and 26'' is also shown.

[0109] Figure 23 A side view of the first coil body 11' is shown (in...) Figure 22 (See view A). The first coil body has an integrated first yoke 17'. Radially extending recesses 26', 26'' and slots 28 for wire threading can be seen.

[0110] from Figure 21 As can be seen in the cross-sectional view, two single-coil assemblies 25' spliced ​​together form a surrounding annular groove 22 centrally located in the region of the opposing first and second yokes 17', 17''. The flanges forming the surrounding annular grooves 22 and the radially extending recesses 26', 26'' enable favorable oil guidance and flow from the radial interior to the radial exterior of the reciprocating piston pump 1'.

[0111] Figure 24 Shown in Figure 20 and Figure 21 An isometric view of the assembly of the single coil assembly 25' of an embodiment of the reciprocating piston pump 1' shown in the figure.

[0112] Figure 25 An end-side view of the assembly of the single coil assembly 25' is shown.

[0113] Figure 26 Shown in Figure 22 and Figure 23 The image shows a cross-sectional view of the coil body 11' with an integrated yoke 17'.

[0114] Figure 27 A cross-sectional view of an assembled single coil assembly 25' is shown, the single coil assembly having a first coil body 11', a first yoke 17', a first housing 16', a first pole plate 15', a first pole core 14', and a first inlet valve 20'.

[0115] Figure 28 A detailed partial view is shown of the area of ​​the sliding surface between the pump piston 19 and the yoke discs 17', 17''. In this embodiment, the pump piston 19 is axially movably guided directly within the yoke discs 17', 17'' without the intervention of a two-piece guide sleeve. Axial movability is indicated by double arrows.

[0116] The pump piston 19 and the yoke discs 17' and 17'' are made of a material with good magnetic permeability. The material has a high relative magnetic permeability. For example, iron (Fe), iron-silicon (FeSi), or free-cutting steel (11SMn30) are used as materials.

[0117] The pump piston 19 has a magnetically insulating coating 19b on its outer surface 19a. The coating 19b also exhibits high wear resistance and good sliding properties. Teflon or chromium nitride coatings are advantageously used as the coating material. The coating typically has a thickness of 25µm to 100µm. During the axial movement of the pump piston 19, the pump piston 19 slides on the inner surfaces 17a', 17a'' of the first and second yoke discs 17', 17'' by means of the coating 19b on its outer surface 19a.

[0118] Alternatively, in the aforementioned implementation variant, the cladding 19b may also be applied to the radially opposite sides of the guide device, i.e., to the inner surfaces 17a' and 17a'' of the yoke.

[0119] In an alternative embodiment, not shown, the pump piston 19 can also be slidably guided directly within a coil body made of plastic, such as PPS + 50 GF / MD. In this variant, it is not necessary to coat the outer surface of the piston with a material having magnetic insulating properties.

[0120] Figure 29 A detailed partial view of the sliding surface region according to the first embodiment is shown, wherein the pump piston 19 is axially movably guided in a two-piece guide sleeve. The two-piece guide sleeve is implemented as first and second bearing bushings 23' and 23''. Axial movement is indicated by double arrows.

[0121] The pump piston 19 and the first and second bearing bushings 23', 23'' are made of a material with good magnetic permeability. The material has a high relative magnetic permeability. For example, iron (Fe), iron-silicon (FeSi), or free-cutting steel (11SMn30) are used as materials.

[0122] The first and second bearing bushings 23', 23'' are preferably thick-walled with a wall thickness of 1 mm to 3 mm.

[0123] The pump piston 19 has a magnetically insulating coating 19b on its outer surface 19a. The coating 19b also exhibits high wear resistance and good sliding properties. Teflon is advantageously used as the coating material. The coating typically has a thickness of 25µm to 100µm.

[0124] During the axial movement of the pump piston 19, the pump piston 19 slides on the inner surfaces 23a', 23a'' of the first and second bearing bushes 23', 23'' by means of the coating 19b on its outer surface 19a.

[0125] Alternatively, in the aforementioned implementation variant, the cladding 19b may also be applied to the radially opposite sides of the guide device, i.e., to the inner surfaces 23a' and 23a'' of the yoke.

[0126] Previously targeted Figure 28 and Figure 29 The described implementation variant has the following advantages: it increases the iron content in the magnetic circuit, which leads to higher power density and minimizes eddy current losses.

[0127] As an alternative implementation, the following design is also feasible. The pump piston 19 is axially movable within a two-piece guide sleeve. The two-piece guide sleeve is implemented as first and second bearing bushings 23' and 23''.

[0128] The pump piston 19 is made of a material with good magnetic permeability. The material has a high relative magnetic permeability. For example, iron (Fe), iron-silicon (FeSi), or free-cutting steel (11SMn30) are used as materials.

[0129] In the design of the first and second bearing bushings 23', 23'', the two-piece guide sleeve is made of a magnetically insulating material with a low relative permeability (µ). r ~ 1). Materials used include, for example, aluminum (Al), (EN AW6062), stainless steel, or brass.

[0130] The pump piston 19 has a magnetically insulating coating 19b on its outer surface 19a. The coating 19b also exhibits high wear resistance and good sliding properties. Teflon is advantageously used as the coating material. The coating typically has a thickness of 25µm to 100µm.

[0131] During the axial movement of the pump piston 19, the pump piston 19 slides on the inner surfaces 23a', 23a'' of the first and second bearing bushes 23', 23'' by means of the coating 19b on its outer surface 19a.

[0132] Alternatively, in the aforementioned implementation variant, the cladding 19b may also be applied to the radially opposite sides of the guide device, i.e., to the inner surfaces 23a' and 23a'' of the yoke.

[0133] List of reference numerals

[0134] 1,1' Reciprocating piston pump

[0135] 2 Pump housing

[0136] 3 Pump Cover

[0137] 4 plugs, electrical interface

[0138] 5 pump inlet

[0139] 6 pump outlet

[0140] 7 suction side

[0141] 8. Pressure side

[0142] 9', 9'' First Exit Passage, Second Exit Passage

[0143] 10 pump shaft

[0144] 11, 11', 11'' coil body, first coil body, second coil body

[0145] 12', 12'' first loop coil, second loop coil

[0146] 14', 14'' first pole core, second pole core

[0147] 15', 15'' First pole plate, Second pole plate

[0148] 16', 16'' first shell, second shell

[0149] 17', 17'' First yoke, Second yoke

[0150] 18', 18'' First elastic element, second elastic element

[0151] 19-pump piston

[0152] 19a outer surface

[0153] 20', 20'' First inlet valve, Second inlet valve

[0154] 21', 21'' First outlet valve, Second outlet valve

[0155] 22 Annular Grooves

[0156] 23', 23'' First bearing bushing, second bearing bushing

[0157] 23a', 23a'' inner surface

[0158] 24, 24', 24'' working chamber, first working chamber, second working chamber

[0159] 25 Dual-coil assembly

[0160] 25' Single Coil Assembly

[0161] 26', 26'' First blank space, Second blank space

[0162] 27 Annular Groove

[0163] 28'', 28'' are the first slot for wire threading, and the second slot is for wire threading.

[0164] 29 Shell web

[0165] 30 valve

[0166] 31 valve housing

[0167] 32 Valve Cover

[0168] 33-valve piston

[0169] 34 First valve spring

[0170] 35 Second Valve Spring

[0171] 36 First Exit

[0172] 37 Second Exit

[0173] 38 penetration part

[0174] 39', 39'' first freewheeling diode, second freewheeling diode

[0175] 40 electrical connector (two poles)

[0176] 41 Electrical Interface (Three-Pole)

[0177] 42 Work Schedule

[0178] 43 cycles

[0179] 44 First Current Curve

[0180] 44' First current curve (positive half-wave)

[0181] 44'' First current curve (negative half-wave)

[0182] 45 Second Current Curve

[0183] 45' Second Current Curve (Positive Signal)

[0184] 45'' Second Current Curve (Negative Signal)

[0185] Q A Part 1: Volumetric Flow

[0186] Q B Part Two: Volumetric Flow

Claims

1. A reciprocating piston pump (1, 1') having a fluid-flowing pump housing (2) and a pump shaft (10), and an axially movable, fluid-flowing pump piston (19), the pump piston being coaxially arranged with two annular coils fixed to the housing, namely a first annular coil (12') and a second annular coil (12''), wherein the reciprocating piston pump (1) has two inlet valves, namely a first inlet valve (20') and a second inlet valve (20''), and two outlet valves, namely a first outlet valve (21') and a second outlet valve (21''). The first inlet valve (20') and the first outlet valve (21') are concentrically arranged within the radial interior of the first annular coil (12') with respect to the pump axis (10), and the second inlet valve (20') and the second outlet valve (21') are concentrically arranged within the radial interior of the second annular coil (12'') with respect to the pump axis (10), and the pump piston (19) is guided in a two-piece volumetric cavity in a two-piece guide sleeve or in a yoke (17', 17'') directly disposed in the pump housing (2).

2. The reciprocating piston pump (1, 1') according to claim 1, characterized in that, The pump piston (19) integrates the functions of an armature that can move and a conveying piston.

3. The reciprocating piston pump (1, 1') according to claim 1 or 2, characterized in that, In the radial interior of the pump housing (2), the first annular coil (12') and the second annular coil (12'') are disposed on a common coil body (11) forming the dual coil assembly (25).

4. The reciprocating piston pump (1, 1') according to claim 1 or 2, characterized in that, Two single-coil assemblies (25') are implemented radially inside the pump housing (2), each single-coil assembly having a ring coil and a separate coil body.

5. The reciprocating piston pump (1, 1') according to claim 3 or 4, characterized in that, Furthermore, as an active electromagnetic component, the dual-coil assembly (25) or the single-coil assembly (25') has a first yoke (17') and a second yoke (17''), with the first yoke disposed on the first annular coil (12') and the second yoke disposed on the second annular coil (12'').

6. The reciprocating piston pump (1, 1') according to claim 5, characterized in that, The first and second yoke disks (17', 17'') are made of a material with good magnetic permeability and high relative permeability, wherein the material is preferably iron (Fe), iron-silicon (FeSi) or free-cutting steel (11SMn30).

7. The reciprocating piston pump (1, 1') according to claim 5, characterized in that, The first and second yoke discs (17', 17'') are connected to a common coil body (11) or a separate coil body (11', 11'') by injection molding encapsulation in the injection molding process.

8. The reciprocating piston pump (1) according to claim 5, characterized in that, The first and second yoke discs (17', 17'') and the common coil body (11) or the separately configured coil bodies (11', 11'') and the yoke discs (11', 11') are implemented in multiple pieces.

9. The reciprocating piston pump (1, 1') according to any one of the preceding claims, characterized in that, As another electromagnetic active component fixed to the housing, the first pole core (14'), the first pole disk (15'), and the first outer shell (16') are disposed on the first annular coil (12'), and the second pole core (14''), the second pole disk (15''), and the second outer shell (16'') are disposed on the second annular coil (12'').

10. The reciprocating piston pump (1, 1') according to any one of the preceding claims, characterized in that, The first and second annular coils (12', 12'') are implemented identically and arranged axially symmetrically on the coil body (11), the first and second annular coils having associated electromagnetic active components, in particular the first and second yokes (17', 17''), or the single coil assembly (25') is symmetrically constructed.

11. The reciprocating piston pump (1, 1') according to any one of the preceding claims, characterized in that, The pump piston (19) is made of a material with good magnetic permeability and high relative permeability, wherein the material is preferably iron (Fe), iron-silicon (FeSi) or free-cutting steel (11SMn30).

12. The reciprocating piston pump (1, 1') according to claim 1, characterized in that, The two-piece guide sleeve consists of a first bearing bushing (23') and a second bearing bushing (23''), wherein the first and second bearing bushings (23', 23'') are made of a material with good magnetic permeability and high relative permeability, wherein the material is preferably iron (Fe), iron-silicon (FeSi) or free-cutting steel (11SMn30), and wherein, more advantageously, the bearing bushings (23', 23'') are thick-walled with a wall thickness of 1 mm to 3 mm.

13. The reciprocating piston pump (1, 1') according to claim 1, characterized in that, The two-piece guide sleeve consists of a first bearing bushing (23') and a second bearing bushing (23''), wherein the first and second bearing bushings (23', 23'') are magnetically insulated and have a low relative permeability (µ). r ~ 1) material implementation, wherein the material is preferably aluminum (Al), (EN AW 6062), stainless steel or brass.

14. The reciprocating piston pump (1, 1') according to any one of the preceding claims, characterized in that, The pump piston (19) is provided with a magnetically insulating coating (19b) on its outer surface (19a) or on its inner surface (23a', 23a'') of the first and second bearing bushings (23', 23''), preferably Teflon or chromium nitride, wherein the coating further advantageously has a layer thickness of 20µm to 100µm.

15. The reciprocating piston pump (1, 1') according to any one of the preceding claims, characterized in that, The valve (30) is connected to the reciprocating piston pump (1, 1') at the output side flange and provides two passages for volumetric flow of fluid.

16. The reciprocating piston pump (1, 1') according to any one of the preceding claims, characterized in that, On the suction side, the flow on the inlet side is guided by a guiding device that guides the fluid in a radial and axial direction around the outer surface of the pump housing (2) and then guides it to the first and second inlet valves (20', 20'').

17. A method for controlling a reciprocating piston pump (1, 1') according to the preceding claims, characterized in that, The pump piston (19) is controlled via current curves (44, 45) with positive and negative current pulses.

18. The method for controlling a reciprocating piston pump (1, 1') according to claim 17, characterized in that, Hydraulic end-position damping is achieved through the orifice plate geometry controlled by the stroke at the pump piston (19).

19. The method for controlling a reciprocating piston pump (1, 1') according to claim 17, characterized in that, Electromagnetic damping is achieved by measuring the current curves (44, 45) of the first and second toroidal coils (12', 12'').

20. The method for controlling a reciprocating piston pump (1, 1') according to claim 17, characterized in that, Short-term overload operation is feasible.

21. The method for controlling a reciprocating piston pump (1, 1') according to claim 17, characterized in that, Active distribution of the transport flow is achieved through temperature-sensitive elements.

22. The method for controlling a reciprocating piston pump (1, 1') according to claim 17, characterized in that, A coil heating device is used to improve low-temperature start-up performance.

23. The method for controlling a reciprocating piston pump (1, 1') according to claim 17, characterized in that, The fluid bottom shell temperature is measured via the voltage drop at the first loop coil (12') and / or the second loop coil (12'').

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