Electromagnetically actuated double-acting piston pump in cartridge design with a mounting system for accommodating two identical coil assemblies

Abstract

The invention relates to an electromagnetically actuated double-acting reciprocating pump (1) in cartridge design, wherein the reciprocating pump (1) has a pump shaft (10), a pump inlet (5), and a pump outlet (6) and comprises the following: a mounting system (31) which holds two identical coil assemblies (25) axially opposite each other in a fixed position, wherein the first coil assembly (25') is configured with a first ring coil (12') and a first fixed armature (13'), and the second coil assembly (25'') is configured with a second ring coil (12'') and a second fixed armature (13''); a pump piston (19) which integrates the function of an armature and a delivery piston and is movably mounted along the pump shaft (10) and is arranged radially inside the first and second coil assemblies (25', 25'') coaxially; and a first and a second displacement chamber (24', 24''). the volume of the displacement chambers changes,when the pump piston (19), designed as an armature, shifts under the action of the coil assemblies (25), two identical inlet valves, namely a first inlet valve (20') and a second inlet valve (20''), and two identical exhaust valves, namely a first exhaust valve (21') and a second exhaust valve (21'').

Description

[0001] The invention relates to an electromagnetically actuated double-acting reciprocating pump in cartridge design for supplying a component of a motor vehicle's drive train with a coolant and / or lubricant, comprising a pump piston axially movable in the direction of a working stroke by an electromagnetic linear drive for displacing and conveying the coolant and / or lubricant, wherein, in the direction of the working stroke, a coil of a solenoid applies an electromagnetic force to the pump piston on both sides, so that the pump piston is electromagnetically actuated on both sides. State of the art

[0002] Electric traction drives typically use oil pumps driven by brushless DC motors (BLDC motors). These pumps deliver a flow rate that can be adjusted as needed, independent of the vehicle speed, by controlling the BLDC motor's speed. The preferred pump type is a rotary positive displacement pump, specifically a gear pump, also known as a gerotor pump. The pump consists of a gear set with an inner and an outer rotor, and a generally two- or three-part pump housing. While this design is simple and proven, it results in high costs for the motor-pump unit, particularly for the BLDC motor and the necessary commutation electronics for motor control, such as the BLDC driver or the B6 bridge rectifier.If the commutation electronics are not integrated directly on the motor, but in a central transmission control unit or the inverter control board of the electric traction machine, additional costs are incurred for the complex cable harness and connectors.

[0003] More cost-effective versions than brushed DC motors can be controlled easily, but due to the sliding contacts they are not wear-free and therefore have a significantly reduced lifespan.

[0004] Mechanically driven oil pumps, for example via an intermediate shaft in the transmission, have the disadvantage that the achievable flow rate depends on the vehicle speed. Therefore, under certain operating conditions, such as high torque and low vehicle speed, an insufficient flow of cooling oil may not be provided. Furthermore, secondary drives that do not have a mechanical disconnect clutch continuously generate drag power.

[0005] Especially for applications in electric secondary drives, where, compared to primary applications, only very small proportions of time are required for active operation over the entire vehicle lifetime, and a generally lower cooling oil requirement is demanded, the above-mentioned designs, known according to the state of the art, do not represent an absolutely satisfactory solution when considering cost and efficiency requirements.

[0006] Furthermore, electromagnetically actuated oscillating piston or diaphragm pumps are already used in other automotive applications. These pumps, generally designed for in-line installation, deliver only very low flow rates. They are used as metering pumps for fuel metering in auxiliary heaters and parking heaters, as AdBlue metering pumps, or as fuel metering pumps for exhaust gas temperature management. However, compared to the eDrive oils used in electric drives, these pumps deliver significantly lower viscosity media, such as diesel or AdBlue. Oscillating piston or diaphragm pumps used as metering pumps are generally designed for very small flow rates, and their operation is often audible. Furthermore, reciprocating piston pumps with electromagnetic drives are known, for example, from German patent application DE 4328621 A1.The electromagnetic drive consists of a magnetic coil, magnetic flux-conducting iron components such as the magnetic pole, iron return, and magnetic yoke, as well as an armature attracted by the stationary magnetic pole. The electromagnetic drive acts on a displacement apparatus in which a dynamically sealed piston enters a displacement chamber and displaces working fluid to the outlet. Simultaneously, the volume of a second chamber, connected to the inlet, is altered. The displacement apparatus typically contains at least two valves: an inlet valve connecting the second chamber to the displacement chamber and an outlet valve connecting the displacement chamber to the outlet.

[0007] According to DE 30 27 539, an electromagnetic piston pump is known in which the piston is moved back and forth by magnetic forces generated by electromagnets. The pump described has a pump housing equipped with electromagnets on both sides and a central section that does not respond to magnetic forces. The piston is made of a material that is attracted to magnetic forces. The piston is moved by alternately switching the electromagnets on and off. A special embodiment is an electromagnetic piston pump that exhibits a double pumping action.

[0008] In the electromagnetic reciprocating pump according to DE 10 2008 055 609 A1, the magnetic armature of the electromagnet that drives the reciprocating pump is mounted by means of an armature rod, which simultaneously performs the function of the displacement piston.

[0009] Furthermore, a reciprocating piston pump with a fluid-filled pump housing and an axially movable, fluid-filled pump piston arranged coaxially to two housing-fixed annular coils is known from the unpublished application with file number 102024202678.6. The pump piston integrates the function of a movable armature (armature of the magnetic circuit) and a delivery piston. The inlet and outlet valves of the reciprocating piston pump are arranged concentrically to the pump axis and radially within the annular coils. The pump piston is guided by a two-part guide sleeve or directly by yoke discs arranged in the pump housing within a two-part displacement chamber.

[0010] The object of the invention is to propose an electromagnetically actuated piston pump with a double-acting, double-acting pump piston in cartridge design, improved in terms of cost and function. Description of the invention

[0011] The problem is solved with an electromagnetically actuated double-acting piston pump in cartridge design with the features according to claim 1.

[0012] The inventive design of the electromagnetically actuated reciprocating pump is cost- and function-optimized compared to previously known reciprocating pumps.

[0013] The pump piston integrates the function of a movable armature (armature of the magnetic circuit) and a pumping piston.

[0014] The pump piston is mounted in a guide sleeve of the reciprocating pump and is double-acting, allowing axial movement in the reciprocating direction.

[0015] By designing the holding system as a radially outer, cage-like component to create an open receiving space for the assemblies and elements of the reciprocating pump, a closed or partially open pump housing can be eliminated. This reduces manufacturing costs and the required installation space in the radial direction.

[0016] Cartridge design means that the pump housing, which is essential for the operation of the reciprocating pump and seals the suction side from the pressure side, is formed by a cavity within the pump's installation space. This cavity is formed by a section of a system housing. The system housing preferably comprises a housing or housing sections of an electric traction drive, which includes an electric motor and a gearbox. Ideally, the reciprocating pump is located in the oil sump (below the nominal fluid level), with the cavity of the system housing, as previously described, serving as a functional component for the pre-assembled reciprocating pump.

[0017] The reciprocating pump design according to the invention exhibits high thermal stability. Heat dissipation from the electromagnetic active components is improved by eliminating the pump housing.

[0018] The coils being completely immersed in the coolant (oil) improve the quality of fluid sump temperature estimation via coil current measurement.

[0019] The two coil assemblies, as well as the inlet and outlet valves, are designed as identical parts, which reduces component variance. This results in a significant cost reduction.

[0020] Advantageously, the pump piston is made of a hybrid construction of plastic and soft iron. This design is advantageous in terms of cost, weight, energy efficiency, and NVH (noise, vibration, and harshness) behavior of the reciprocating piston pump.

[0021] The pump piston is a multi-part design comprising an anchor body made of a plastic material and two iron anchor rings. The anchor body of the pump piston is preferably manufactured as a cost- and weight-optimized injection-molded plastic part, enabling functional integration of the valve guides for the exhaust valves, thus eliminating the need for additional components.

[0022] The piston assembly features a hybrid piston as an armature body made of a magnetically non-conductive material, with iron rings arranged opposite each other in the axial direction. This design completely decouples the two electromagnetic circuits, thus preventing magnetic leakage fluxes in the moving armature. The base body is preferably manufactured from a plastic using an injection molding process.

[0023] In a preferred embodiment, the iron rings can be overmolded with plastic during the production of the plastic carrier of the piston assembly using injection molding, or in an alternative embodiment, the iron rings can be pressed onto the plastic carrier.

[0024] Furthermore, the piston assembly can be advantageously designed in such a way that the plastic carrier is produced in the injection molding process with axially opposing rings with co-injected iron particles.

[0025] Advantageously, the plastic carrier of the piston assembly is designed with integrated valve guides. This simplifies assembly.

[0026] The two separate, radially external coil assemblies completely decouple the two housing-mounted electromagnetic circuits, thus preventing magnetic stray fluxes in the housing-mounted components.

[0027] A further advantage is that the design of the reciprocating pump according to the invention allows for scalability. The double-coil pump can be scaled for different requirements and applications with regard to copper usage (cost), power consumption, and achievable pressure level by adjusting the coil parameters such as wire diameter, number of layers, and number of windings per layer. Description of the characters Fig. Figure 1 shows a hydraulic circuit diagram of an electromagnetically actuated reciprocating piston pump according to the invention. Fig. Figure 2 shows an isometric view of an exemplary embodiment of the electromagnetically actuated reciprocating pump according to the invention. Fig. Figure 3 shows another isometric view of the electromagnetically actuated piston pump according to the invention. Fig. 2. Fig. Figure 4 shows a front view looking at the inlet-side filter screen of the in Fig. 2 and Fig. 3 shown reciprocating piston pump. Fig. 5 shows a front view looking at the pump cover of the in Fig. 2 and Fig. 3 shown reciprocating piston pump. Fig. Figure 6 shows a longitudinal view of the in Fig. 2-5 illustrated reciprocating piston pump. Fig. Figure 7 shows a first sectional view along the in Fig. Section plane AA shown in section 5. Fig. Figure 8 shows a second sectional view along the in Fig. Section plane BB shown in section 6. Fig. Figures 9a and 9b show the multi-part piston as an exploded view in isometric view and in a longitudinal section view (section AA in Fig. 7). Fig. Figures 10a and 10b show the piston assembly as an exploded view in isometric view and in a longitudinal section view (section AA in Fig. 7). Fig. Figures 11a and 11b show the fixed anchor assembly as an exploded view in isometric view and in a longitudinal section view (section AA in Fig. 7). Fig. Figure 12 shows an isometric view of the pump cover in a first embodiment. Fig. Figure 13 shows an isometric view of the pump cover in a further embodiment. Fig. Figure 14a shows a representation of the mounting bracket of the reciprocating pump in a first isometric view. Fig. Figure 14b shows a representation of the mounting bracket of the reciprocating pump in a second isometric view. Fig. Figure 15 shows a representation of the filter sieve. Fig. Figure 16 shows an exemplary section of a system housing with a corresponding cavity for receiving the reciprocating piston pump according to the invention. Fig. 17 shows a frontal view of the in Fig. 16 shown housing section (view A in Fig. 16). Fig. Figure 18 shows a longitudinal section view of the in Fig. 16 and Fig. 17 shown housing section (section CC in Fig. 17). Fig. Figure 19 shows a negative model of the flow path in longitudinal section (section AA in Fig. 7)

[0028] Fig. Figure 1 shows a hydraulic circuit diagram of an electromagnetically actuated double-acting piston pump 1 according to the invention, with a suction side 7 and a pressure side 8. A pump piston 19 is actuated via a first winding 12' of a coil assembly designed as a ring coil and a second winding 12" of a coil assembly designed as a ring coil.

[0029] In the illustrated embodiment of the double-acting piston pump 1, the pump piston 19 can be actuated from both sides in the axial direction and is actuated in two directions via a double-coil solenoid by the alternating electromagnetic force of the double-coil arrangement. The direction of movement of the pump piston 19 is indicated by the double arrow PF pointing in the Fig. 7 and Fig. 8 displayed.

[0030] Fig. Figures 2-8 show an embodiment of the electromagnetically actuated double-acting reciprocating pump 1 according to the invention. The reciprocating pump 1 has a pump axis 10. In the context of the present invention, axial means in the direction of the pump axis 10.

[0031] In the Fig. Figures 16-18 show a section of a system housing in various views / sections, which shows a housing area with a corresponding cavity for receiving the reciprocating pump according to the invention. As described in more detail below with reference to the figures, the cavity functions as the pump housing of the reciprocating pump 1. The reciprocating pump 1 is designed in a cartridge design; a separate pump housing is not required.

[0032] Fig. 2 and Fig. Figure 3 shows isometric views of the reciprocating pump 1 with a holding / mounting system 31, which accommodates two identical coil assemblies 25', 25" opposite each other in the axial direction. The reciprocating pump 1 has a filter screen 32 as a cover element on the first end face, and the opposite second end face of the reciprocating pump 1 is closed by a pump cover 3. The pump cover 3 is equipped with a connector 4 for electrical contact.

[0033] As can be seen from the Fig. 2 and Fig. 3 is the inlet of the reciprocating pump 1, marked with the arrow IN. This is located on the first end face of the reciprocating pump 1 in the area of ​​the filter screen 32. The inlet forms the suction side. The pump outlet is marked with the arrow OUT and, viewed axially, is located centrally in the area of ​​the mounting system 31, with a flow direction extending radially outwards.

[0034] Fig. Figure 4 shows a view of the first end face of the filter screen 32, which forms the pump inlet 5 and the suction side 7.

[0035] Fig. Figure 5 shows a view of the opposite second end face of the piston pump 1. The second end face is formed by the pump cover 3 with connector 4.

[0036] Fig. Figure 6 shows a longitudinal view of the reciprocating piston pump 1, in Fig. 8 is a section along the section line BB according to Fig. Figure 6 shows the first and second clamping contacts 33', 33" with their associated first and second electrically conductive connections 34', 34" from this illustration. These extend from the connector 4 and corresponding contact points in the area of ​​an outer surface for contacting the first and second windings 12', 12" of the first and second coil assembly 25', 25".

[0037] The Fig. 7 and Fig. Figure 8 shows the structure of the reciprocating piston pump 1 in two different sectional views, which is described in more detail below.

[0038] The electromagnetic active components of the reciprocating pump 1 include two identical coil assemblies 25', 25': two pole cores, two pole discs, two sheaths, two yoke discs, and two ring coils (coil former and winding). The arrangement of these components is described in more detail below with reference to the sectional drawings. The electromagnetic active components are fixedly connected to the holding / mounting system 31 and arranged in an open receiving space formed by retaining tabs, as described in more detail below. A pump housing is omitted, which ensures good heat dissipation by the surrounding fluid, preferably oil.

[0039] On the inlet side, the fluid, preferably oil, is guided via the filter screen 32 to a first and a second inlet valve 20', 20" of the reciprocating pump 1. As can be seen from the sectional views of the Fig. 7 and Fig. As can be seen in Figure 8, the first inlet valve 20' is located on the left side of the pump piston 19 when viewed axially in the direction of the reciprocating pump 1, and the second inlet valve 20" is located on the right side of the pump piston 19. This achieves a double-acting operating principle with the pump piston acting on both sides, as well as a defined flow around and convective heat dissipation of the electromagnetic active parts of the pump, both on the suction and pressure sides, radially inside and radially outside, via the operating medium.

[0040] The pump piston 19 is shown in the exploded view of the Fig. 9a is shown, is made in multiple parts and comprises a hollow cylindrical armature body 28 as well as a first and second armature iron ring 29', 29". The pump piston 19 simultaneously acts as a movable armature of the two electromagnetic circuits.

[0041] Fig. Figure 9b shows the pump piston 19 in a sectional view. It can be seen that the first anchor iron ring 29' is arranged on the lateral surface of a first end region of the pump piston 19 and the second anchor iron ring 29" is arranged on the lateral surface of an opposite second end region of the pump piston 19.

[0042] The armature body 28 is preferably manufactured as a plastic injection-molded part, whereby the two armature iron rings 29', 29" can be directly overmolded as inserts. This allows manufacturing costs to be kept low and the required dimensional, form, and positional tolerances to be ensured. In addition, the mass of the moving parts can be minimized and electromagnetic stray flux between the two electromagnetic circuits via the armature can be prevented, which in turn increases the efficiency of the electromagnetic drive.

[0043] The anchor iron rings 29', 29" are formed at their ends with a control cone 29a. Annular circumferential grooves 30 are provided on the anchor iron rings 29', 29". The first circumferential groove 30, located at the end of the control cone 29a of the anchor iron rings, serves as a dirt-trapping groove. The other annular circumferential grooves 30 on the anchor iron rings serve as pressure relief and dirt-trapping grooves and additionally increase the robustness of the pump piston 19 (movable anchor) against jamming by dirt particles.

[0044] In an alternative embodiment, permanent magnet rings or bar magnets can be overmolded or integrated into the armature body 28 instead of the armature iron rings, thereby further increasing the power density of the electromagnetic linear drive. Preferably, the permanent magnets are magnetized after overmolding or assembly with the armature body 28.

[0045] Furthermore, an alternative design of the pump piston 19 is possible as a one-piece anchor body 28 manufactured in a plastic injection molding process, which contains ring areas circumferential on both sides with iron particles injected into it.

[0046] The Fig. 10a and Fig. Figure 10b shows a piston assembly 35 consisting of the pump piston 19, a first exhaust valve 21', and a second exhaust valve 21". The first and second exhaust valves 21' and 21" each comprise a valve spring 39 and a valve seat 41. The first and second exhaust valves 21' and 21" are each spring-loaded at their end faces into the corresponding cylindrical bore and axially secured at their ends by the annular valve seat 41 within the cylindrical bore. The piston assembly 35 can be easily pre-assembled. The valve seats 41 can be manufactured as cost-effective stamped sheet metal parts with clip mounting.

[0047] As can be seen from the sectional views of the Fig. 7 and Fig. As can be seen in Figure 8, the pump piston 19 or the piston assembly 35 is mounted in a guide sleeve 22 so as to be slidably displaceable in the axial direction.

[0048] The piston assembly 35 is guided with minimal radial clearance (on the order of 0.01 to 0.03 mm) in the guide sleeve 22. The guide sleeve 22 is thin-walled (on the order of 0.7 mm wall thickness) and made of a non-magnetic material. Suitable materials include, for example, stainless steel, aluminum, or brass. Viewed axially, the guide sleeve 22 preferably has several radial openings in its center for the exhaust-side oil flow.

[0049] The reciprocating piston pump 1 according to the invention comprises two identical coil assemblies, namely a first coil assembly 25' which has a first winding 12' arranged around a first coil former 11', a first fixed armature 13' consisting of a first pole core 14' and a first pole disk 15', a first yoke disk 17' and a sheath 16' radially enclosing the first coil assembly. The second coil assembly 25" comprises a second winding 12" arranged around a second coil former 11", a second fixed armature 13" consisting of a second pole core 14" and a second pole disk 15", a second yoke disk 17" and a sheath 16" radially enclosing the second coil assembly. The fixed armature 13, which in the illustrated embodiment consists of a pole core 14 and a pole disk 15, can also be made in one piece. In the two-part design shown, the two parts are connected by force-fit, e.g.via a cross-cut joint or positive locking, e.g. via a laser welding connection.

[0050] The Fig. Figure 11a shows an exploded view of a fixed armature assembly 44 with fixed armature 13 and inlet valve 20. The fixed armature assembly shown is used in the reciprocating pump, as can be seen from the assembly of the Fig. 7 and Fig. As can be seen in section 8, it is installed twice, namely as the first and second fixed anchor assembly, which includes the first and second fixed anchor 13', 13" and the first and second inlet valve 20".

[0051] The fixed anchor 13 contains an inlet valve 20 which is preloaded between the valve guide 40 and the valve seat 41 by a valve spring 39. The valve guide 40 is designed as a cover-shaped element with a centrally located axial through-hole and further comprises hook-shaped elements 40a. By means of the hook-shaped elements 40a, the valve guide is clipped to the end region of the pole core 14 via corresponding detents and axially fixed. The valve seat 41 is designed as a cover-shaped element with a centrally located axial through-hole and further comprises hook-shaped elements. By means of the hook-shaped elements, the valve seat 41 is clipped into a central through-hole of the pole disk and axially fixed.The previously described clip connections between valve guide / pole piece and valve seat / pole disc enable cost-efficient manufacturing and assembly of the components, which can be designed as identical parts.

[0052] The valve seats 41 can be designed as cost-effective sheet metal stamped and embossed parts with clip mounting. The valve guide 40 arranged on the fixed armature further comprises a stop damping element 38, which is preferably designed as an elastomer molded element overmolded onto the valve guide 40. In this way, the air gap of the electromagnetic circuit can be limited in the end position and the impact of the pump piston 19 in the end position can be dampened. The fixed armature 13 and the functional components of the inlet valve 20 can be pre-assembled as a fixed armature assembly 44 ( Fig. 11 a, b).

[0053] The Fig. Figure 12 shows the pump cover 3 in a first embodiment. The pump cover 3 includes the connector 4, which forms the electrical connection with the overmolded busbars for the electrically conductive connection (45, 46) to the first and second windings 12', 12". The busbars 45, 46 can be connected to the wire ends of the first and second windings 12', 12" by means of a crimp connection or by means of a solder or weld connection.

[0054] The Fig. Figure 13 shows the pump cover 3 in a second embodiment as a clamp-plug connection. As an alternative to the variant described above, clamping contacts 47, 48 integrated into the coil body are provided for the electrically conductive connection of the busbars 45, 46 and the first and second windings 12', 12".

[0055] The busbars can, as in the Fig. 12 and Fig. As described in section 13, the pump cover is overmolded as a plastic injection-molded part during its manufacture. Alternatively, the busbars can be guided through the pump cover 3, which is made of a plastic material, to the connector 4 via an additional sealing element.

[0056] As an alternative to the intended connector 4, the busbars 45, 46 can be routed directly within the system housing 53 to the electrical power output stage, which is integrated, for example, in an add-on control unit or in the inverter control board of an electric traction machine, so that an externally routed electrical interface that can be disconnected by means of a plug connection can be completely omitted.

[0057] The Fig. 14a and Fig. Figure 14b shows the mounting system 31 in a first and second isometric view. As can be seen from the illustrations, the mounting system 31 comprises a central annular element 31a, and extending axially to the right and left from the central annular element, three elongated first and second tabs 31b are formed on the outer circumference of the annular element 31a, forming a first clamp half 72' and a second clamp half 72". The first and second tabs 31b are arranged evenly distributed around the circumference. The end regions of the first and second tabs are curved radially inwards and form first and second hooks 74', 74". The first and second clamp halves form a cylindrical, partially open receiving space for the first and second coil assemblies 25', 25".

[0058] The central ring-shaped element 31a, as can be seen from the Fig. As can be seen in Figure 14a, two parallel, radially outwardly projecting tabs 75 are formed on the underside (relative to the installation situation in the housing cavity). On the opposite side of the central annular element 31a, a radial bore is provided, which forms the pump outlet 6 and is associated with the pressure side 8. The radial bore 6 is surrounded by a sealing surface 73 extending along the casing.

[0059] Fig. Figure 15 shows a perspective view of the filter screen 32. The filter screen 32 is lid-shaped and has a radially outer circumferential rim. The rim is provided with fastening lugs 51, which are preferably integrally formed. During assembly, the filter screen 32 is attached on the suction side, in the inlet area of ​​the pump 1, via the fastening lugs 51 to the end regions of the first tabs 31b' of the mounting bracket 31 of the reciprocating pump 1. This allows the reciprocating pump 1 and the filter screen 32 to be pre-assembled as a unit ( Fig. 7 and Fig. 8) This reduces the effort required for handling and mounting the pump 1 in the system housing 53. Furthermore, the filter screen 32 is provided with a circumferential sealing lip 52 on the edge area opposite the mounting lugs 51. Alternatively, the filter screen 32 can be overmolded with an elastomer molded element in the area of ​​the axial sealing surface to the system housing, thereby compensating for tolerance influences.

[0060] Fig. Figure 16 shows an exemplary section of a system housing 53 with a corresponding cavity 54 for receiving the reciprocating piston pump 1 according to the invention. The pre-assembled reciprocating piston pump 1 is inserted into the cavity 54 in the direction of arrow A during final assembly and screwed to the corresponding mounting points with threaded holes 56 on a flange surface 55 in the system housing 53 via the mounting tabs with bores and corresponding screws molded into the pump cover 3.

[0061] The system housing 53, for example the electric motor or gearbox housing of the electric drive, forms a functional part of the reciprocating piston pump 1 according to the invention. The reciprocating piston pump 1 is received in a housing cavity, preferably arranged in an area below the oil sump ( Fig. 16) The reciprocating pump 1 is arranged entirely within the cavity 54, and preferably below the fluid sump level. Sealing to the outside is achieved via a sealing element 42 located between the flange surface 55 and the pump cover 3. The sealing element 42 can be a commercially available O-ring or any other shaped sealing element, e.g., a flat gasket.

[0062] Since the housing cavity 54 for receiving the reciprocating piston pump 1 is preferably located on a z-direction (coordinate axis see Fig. 17, Fig. 18) is located in the lowest position of the system housing, an additional oil drain plug can be omitted, which contributes to additional cost savings.

[0063] As can be seen from the Fig. As can be seen in Figure 18, the housing cavity 54 includes a first centering bore 57 for receiving the cartridge-type reciprocating pump 1 according to the invention via the mounting system 31. This bore 57 serves not only as a centering bore but also as a sealing bore, preventing the suction and pressure side fluid areas from one another. When the reciprocating pump 1 is mounted in the housing cavity 54, the outer sealing surface 73 of the fluid outlet bore in the mounting system 31 abuts the inner wall of the housing with respect to the centering bore 57 in such a way that the fluid outlet bore in the mounting system 51 aligns with an outlet bore 61 in the system housing 53, which opens into the first centering bore 57 and is preferably located at the top in the z-direction. The outlet bore 61, preferably located at the top in the z-direction, ensures effective self-venting of the pump.

[0064] Furthermore, the housing cavity 54 includes a second centering bore 58, which serves to receive and center the pump cover 3. For a compact design, the two centering bores 57, 58 are arranged eccentrically to each other (eccentricity e in Fig. 18). The recess 59 arranged in the first centering bore serves as a clearance for the busbars 45, 46 integrated in the overmolding 49 of the pump cover 3 for the first and second winding 12', 12" and for preventing rotation of the piston pump 1 via the radially outward projecting tabs 75 molded onto the mounting bracket 31.

[0065] Furthermore, the first centering bore 57 is in direct communication with an oil sump area 60 of the system housing 53. This area forms the pump inlet IN. An axial end face 71 provided at the inlet-side end of the first centering bore 57 serves to receive the filter screen 32. A sealing element arranged on the filter screen 32, preferably a sealing lip 52 integrated in the filter screen 32 or an elastomer seal overmolded as a soft component, serves to compensate for axial tolerances between the pump assembly and the housing cavity.

[0066] Fig. Figure 18 shows a longitudinal section view of the in Fig. 16 and Fig. 17 shown housing section (section CC in Fig. 17).

[0067] Fig. Figure 19 shows a longitudinal section and a negative model of the flow path - section plane AA in Fig.5 - through the reciprocating piston pump 1 along the pump axis 1. The light gray areas symbolize the fluid volume of the suction side 62, the dark gray areas symbolize the fluid volume 67 of the pressure side. The pump piston 19 is shifted axially to the right, and the fluid volume within the displacement chamber 68 formed on the delivery stroke side is reduced, thus compressing the fluid contained therein (top dead center). The fluid volume within the displacement chamber 64 formed on the suction stroke side is increased and shows its maximum intake volume (bottom dead center). Starting from the pump inlet IN, the fluid volume in the region of the pump inlet 63 is shown. Through the first inlet valve 20' and the stroke movement of the pump piston to the right, fluid is drawn into the first displacement chamber 24'. The fluid volume in this region is labeled 64.On the suction side, the illustration shows that a fluid volume forms in the area of ​​the pump casing 65 and a fluid volume forms in the area of ​​the pump cover 66, which enables good heat dissipation and cooling of the electromagnetic active parts via the fluid.

[0068] In the area of ​​the second inlet valve 20" and the fluid-connected second displacement chamber 24" connected to it, the pressure side is formed in this depicted situation via the reduced volume of the second displacement chamber 24". The fluid volume within the displacement chamber formed on the delivery stroke side is designated by reference numeral 68. The fluid flows via the first outlet valve 21' and the second outlet valve 21" on the pressure side to the pump outlet 6 in the central section of the assembly system 31 on the pressure side 8. The fluid volume in the area of ​​the outlet channel is indicated by the areas designated by 69. The fluid volume in the area of ​​the outlet bore has reference numeral 70. Reference sign 1 Electromagnetic pump 3 pump covers 4 plugs, electrical connection 5 Pump inlet 6 Pump outlet 7 Suction side 8 printed page 9, 9', 9" exhaust port, first exhaust port, second exhaust port 10 Pump shaft 11, 11', 11" coil former, first coil former, second coil former 12, 12', 12" winding, first winding, second winding 13, 13', 13" fixed anchor, first fixed anchor, second fixed anchor 14, 14', 14" pole piece, first pole piece, second pole piece 15, 15', 15" pole plate, first pole plate, second pole plate 16, 16', 16" coat first coat, second coat 17, 17', 17" yoke disc, first yoke disc, second yoke disc 18, 18', 18" Elastic element, first elastic element, second elastic element 19 pump pistons 20, 20', 20" Inlet valve, first inlet valve, second inlet valve 21, 21', 21" exhaust valve, first exhaust valve, second exhaust valve 22 Guide sleeve 24, 24', 24" displacement chamber, first displacement chamber, second displacement chamber 25, 25', 25" coil assembly, first coil assembly, second coil assembly 26, 26', 26" recess, first recess, second recess 27 Ring groove 28 anchor bodies 29, 29', 29" anchor ring, first anchor ring, second anchor ring 29a Tax cone 30 grooves 31 Mounting system 31a central ring-shaped element 31b Tabs 32 filter screens 33, 33', 33" terminal contacts, first terminal contact, second terminal contact 34, 34', 34" electrically conductive connection (bus bars) 35 Piston assembly 36 clip connection, first clip connection, second clip connection 37 Valve guide 38 Impact damping, damping ring 39 Valve spring 40 Valve guide 40a hook-shaped elements 41 Valve seat 42 O-ring 43 plug-in punch grids, bus bars 44 Fixed anchor assembly 45 busbars for first winding 46 busbars for second winding 47 clamping contacts for first winding 48 terminal contacts for second winding 49 Re-injection 50 hooks 51 fastening lugs 52 Lip for axial tolerance compensation 53 system enclosures 54 case cavity 55 flange area 56 threaded hole 57 first centering bore 58 second centering hole 59 recess 60 Oil sump area 61 Outlet bore 62 Fluid volume on suction side (negative geometry) 63 Fluid volume in the area of ​​the pump inlet 64 Fluid volume within the displacement chamber formed on the suction stroke side 65 Fluid volume in the area of ​​the pump casing 66 Fluid volume in the area of ​​the pump cover 67 Fluid volume on the pressure side (negative geometry) 68 Fluid volume within the displacement chamber formed on the conveying stroke side 69 Fluid volume in the area of ​​the outlet channel 70 Fluid volume in the area of ​​the outlet bore 71 Axial end face of the first centering bore 72, 72', 72" bracket, first half of bracket, second half of bracket 73 Sealing surface 74 hooks 75 Tab for anti-rotation device INflowing cooling / lubricating oil stream OUT outflowing cooling / lubricating oil flow eccentricity z vertical coordinate axis along the vehicle's vertical axis PF Double Arrow QUOTES INCLUDED IN THE DESCRIPTION

[0000] This list of documents cited by the applicant was automatically generated and is included solely for the reader's convenience. The list is not part of the German patent or utility model application. The DPMA accepts no liability for any errors or omissions. Cited patent literature

[0000] DE 4328621 A1

[0006] DE 30 27 539

[0007] DE 10 2008 055 609 A1

[0008]

Claims

Electromagnetically actuated double-acting reciprocating pump (1) in cartridge design, wherein the reciprocating pump (1) has a pump shaft (10), a pump inlet (5), and a pump outlet (6) and comprises the following: a mounting system (31) which axially supports two identical coil assemblies (25) opposite each other, wherein the mounting system (31) comprises a central annular element (31a) which forms the pump outlet (6), wherein extending axially from the outer circumference of the central annular element (31a) on both sides are a first clamp half (72') and a second clamp half (72") which form a cylindrical receiving space for the first and second coil assemblies (25', 25"), wherein the first coil assembly (25') comprises a first ring coil (12') and a first fixed armature (13'), and the second coil assembly (25") comprises a second ring coil (12") and a second fixed anchor (13") are designed,a pump piston (19) which integrates the function of an armature and a delivery piston and is movably mounted along the pump axis (10), and is arranged radially inside the first and second coil assemblies (25', 25"), a first and a second displacement chamber (24', 24"), wherein the volume of the displacement chambers changes when the pump piston (19), designed as an armature, moves under the action of the coil assemblies (25), two identical inlet valves, namely a first inlet valve (20') and a second inlet valve (20"), two identical outlet valves, namely a first outlet valve (21') and a second outlet valve (21"). Electromagnetically actuated double-acting piston pump (1) in cartridge design according to claim 1, characterized in that the first and second clamp halves (72', 72") are each formed from three elongated first and second tabs (31b) formed on the outer circumference of the annular element (31a), wherein the end regions of the first and second tabs (31b) preferably form first and second hooks (74', 74"). Electromagnetically actuated double-acting piston pump (1) in cartridge design according to claim 1 or 2, characterized in that the pump piston (19) is designed as a hybrid component made of different materials. Electromagnetically actuated double-acting piston pump (1) in cartridge design according to claim 3, characterized in that the pump piston (19) is multi-part and comprises a hollow cylindrical armature body (28) as a plastic injection-molded part, as well as a first and second armature iron ring (29', 29"), wherein the first armature iron ring (29') is connected to a first end region of the armature body (28) and the second armature iron ring (29") is connected to an end region of the armature body (28) opposite the first end region, wherein the connection is preferably made via a material-bonded connection and the armature iron rings (29', 29") are manufactured as insert parts in plastic injection molding. Electromagnetically actuated double-acting piston pump (1) in cartridge design according to claim 4, characterized in that the armature iron rings (29', 29") are formed at their ends with a control cone (29a), and preferably annular circumferential grooves (30) are provided on the armature iron rings (29', 29"). Electromagnetically actuated double-acting piston pump (1) in cartridge design according to claim 3, characterized in that the pump piston (19) comprises a hollow cylindrical armature body (28) made of a plastic material and at each end a permanent magnet ring or bar magnets which are bonded to the armature body via the plastic material. Electromagnetically actuated double-acting piston pump (1) in cartridge design according to claim 3, characterized in that the pump piston (19) is manufactured in one piece using a plastic injection molding process and has a hollow cylindrical armature body (28) with end-opposite circumferential ring areas with ferrous metallic or permanent magnetic particles injected into it. Electromagnetically actuated double-acting piston pump (1) in cartridge design according to one of the preceding claims, characterized in that the pump piston (19) with first and second outlet valve (21', 21") forms a piston assembly (35), wherein first and second outlet valve (21', 21") are axially secured radially opposite each other within the pump piston (19) in receiving bores of the armature body (28). Electromagnetically actuated double-acting piston pump (1) in cartridge design according to one of the preceding claims, characterized in that the first fixed armature (13') with first inlet valve (20') and second fixed armature (13") with second inlet valve (20") each form an identical fixed armature assembly (44), wherein the inlet valves (20', 20") are held radially within the fixed armatures (13', 13") axially secured. Electromagnetically actuated double-acting piston pump (1) in cartridge design according to one of the preceding claims, characterized in that the piston pump (1) has a first and second end face and the pump inlet is formed on the first end face and the end face is covered by means of a filter screen (32) and held on the first clamp half (72') via a clip connection. Electromagnetically actuated double-acting piston pump (1) in cartridge design according to claim 10, characterized in that the second end face is sealed to the outside by means of a pump cover 3, wherein the pump cover (3) comprises a plug (4) for electrical contact with first and second busbars (45, 46) for contact with first and second ring coils (12', 12") of the first and second coil assembly (25', 25"). Electromagnetically actuated double-acting piston pump (1) in cartridge design according to claim 11, characterized in that the pump cover (3) comprises molded mounting tabs with through holes. System comprising an electromagnetically actuated double-acting reciprocating pump (1) in cartridge design according to one of the preceding claims, and a housing cavity (54) of a system housing of an electric traction drive with electric motor and gearbox unit, wherein the reciprocating pump (1) is arranged in the housing cavity (54) such that a suction and pressure side area is formed, wherein the sealing in the area of ​​the pump outlet (6) in the mounting system (31) is effected via a shell-side sealing surface (73) on a housing wall of the housing cavity and the pump outlet (6) opens into a fluid bore in the housing wall.

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