EP3279476A1 - Electrohydraulic machine with integrated sensor - Google Patents

Abstract

The invention relates to an electrohydraulic motor-pump unit (1), MPE, with a pump (10) for conveying a hydraulic fluid in a hydraulic system (HS), an electric motor (20) coupled to the pump (10) for driving, with the control unit (30) coupled to the electric motor (20) and for controlling and / or regulating the electric motor (20) and a housing (50), wherein at least one sensor (70) is integrated in a sensor receptacle (80) integrated in the housing (50). 71, 72) and is electrically connected to the controller (30). Furthermore, the invention relates to a hydraulic system (HS) comprising hydraulic lines (HL) and to the hydraulic lines (HL) connected MPE (1) of the invention with at least one integrated pressure sensor.

Description

The invention relates to an electrohydraulic machine, in particular an electrohydraulic motor-pump unit, for conveying hydraulic fluid in a hydraulic system with at least one integrated sensor.

background

An electrohydraulic machine is understood here to mean a machine which has a pump unit, a drive unit and an associated control unit, referred to for short as "power pack" and in the following as "motor-pump unit (MPE)". In an MPE, different hydraulic pump types can be used for the pump unit and different electric motors for the drive unit. First, an MPE is primarily designed to convert electrical energy into hydraulic energy. Areas of application for MPEs are, for example, modern electric automobiles, mobile working machines and, more generally, the industrial sector. MPEs may also be operated in a generator mode depending on the electric motor used, so that hydraulic energy from the hydraulic circuit can be converted into electrical energy, that is, MPEs that can operate in both engine operation and generator operation are also known.

For example, in applications in the automotive sector, pressure in hydraulic high pressure systems has typically been generated by a hydraulic pump coupled to the internal combustion engine. This is no longer possible with hybrid or electric vehicles, as an internal combustion engine either not always running or missing. Therefore, in the future, hydraulic pressures will be generated by self-contained electro-hydraulic units, such as an MPE. With MPEs, which can also be operated in a generator mode, energy from the hydraulic circuit can be fed back into the electrical system as electrical energy. Especially for the automotive sector there are special requirements for MPEs, such as: B. very compact, space and weight-saving design, high efficiency, long service life under continuous use, integrated design, zero maintenance and the like.

For example, shows DE 102 54 670 A1 a compact arrangement between motor and pump housing. DE 10 2014 103 959 A1 and the DE 10 2014 103 958 A1 each describe a motor-pump unit for use in chassis systems of motor vehicles, wherein the motor and the pump are compactly integrated with each other.

The pressure prevailing in the hydraulic system pressure can be detected by a pressure sensor and reported as an actual state variable to the electronic control unit MPE for further use. For pressure detection, a pressure sensor is usually provided in a valve block or an adapter piece within the hydraulic line network usually. To supply the pressure sensor electrically and to transmit a pressure measurement signal to the electronic drive unit, it is usually electrically connected via an electrical wiring or a wiring harness to the electronic drive unit.

For applications in the vehicle exterior, z. B. in the underbody area, the pressure sensors and their mechanical and electrical integration must be protected accordingly against corrosion and against mechanical effects such as rockfall.

Summary of the invention

The object of the invention is to improve known MPEs with regard to the provision of sensor signals to the control or regulation device of an MPE.

The object is achieved in each case with the respective features of one of the independent claims. Further embodiments and advantageous developments are defined in the respective subsequent subclaims. In this case, features and details which are described in connection with the MPE according to the invention apply, of course also in connection with a hydraulic system with the MPE according to the invention and in each case vice versa. Therefore, mutual reference is made to the disclosure of the individual aspects.

The essence of the invention lies in a constructive integration we least one sensor, such as a pressure sensor, directly into the MPE, preferably in the pump housing. Thus, the sensor signal can already be provided during the manufacture of the MPE to a control unit or control unit of the MPE and already tested together with the MPE.

A first aspect of the invention thus relates to an electro-hydraulic motor-pump unit, MPE, with a pump for conveying a hydraulic fluid in a hydraulic system, an electric motor coupled to the pump for driving, coupled to the electric motor and set up to drive the electric motor control and a housing. According to the invention, the MPE knows at least one in one integrated into the housing Sensor receiving arranged and electrically connected to the sensor sensor.

It should be noted that the controller for controlling the electric motor of the MPE can also be configured so that the electric motor and thus the driven pump can be regulated in terms of a regulation with respect to one or more target variables taking into account one or more state variables ge. The term control is thus not to be understood as excluding the functionality "regulation". Rather, "control" here covers both the influencing of a target variable and also with feedback.

Preferably, the at least one sensor is shielded from the outside by the housing or a corresponding housing part of the MPE from the outside world. Thus, the sensor can be protected by the housing against environmental influences. Also, the sensor is no longer visible from the outside.

The at least one sensor may, for example, be a pressure sensor which is in pressure-sensoric contact with a fluid conveyed during operation of the MPE. For this purpose, the pressure sensor can be in pressure-sensitive contact with the pumped fluid, for example, at a fluid connection of the MPE.

The pump can be an internal gear pump. Internal gear pumps are for example from the DE 43 38 875 A1 or the EP 1 192 375 A1 known and work according to the displacement principle. In essence, an internal gear pump consists of three components, a pump housing, a driven pinion gear with external teeth, a toothed ring gear (ring gear) with internal teeth and a housing fixed integrated crescent-shaped filler (sickle), preferably symmetrical to a median plane between the Pinion and the ring gear formed is and forms with the teeth of the pinion and the ring gear tooth chambers. The pinion and the ring gear run eccentrically, wherein the fluid to be delivered is conveyed substantially in the tooth chambers. The axial extent of the sickle coincides with the axial extent of the pinion and the ring gear. For axial sealing between the gears and the pump housing on each side an axial pressure plate is arranged, which is pressed in each case by a Axialdruckfeld generated between the Axialdruckplatte and the pump housing axially against pinion and ring gear. The Axialdruckplatten have holes which are penetrated by a drive shaft for the pinion, and are thereby arranged in a plane perpendicular to the axes of the gears. An axial pressure field is formed either in a recess in the pump housing or on the housing side in the axial pressure plate and compared to the sickle semi-sickle-shaped, so that the Axialdruckfeld extends only on one side of the median plane of the sickle. Each Axialdruckfeld is connected, for example via a bore in the Axialdruckplatte depending on the conveying direction of the pump with the suction chamber or pressure chamber of the pump. There is no connection between the two axial pressure fields on an axial pressure plate, ie, depending on the conveying direction of the pump, the high pressure generated by the pump is built up in an axial pressure field of the axial pressure plates.

When the pump is designed as an internal gear pump, the at least one pressure sensor can be in pressure-sensitive contact with the pumped fluid at an axial pressure field of the pump.

It should be noted that a pressure sensor via a check valve interconnection can always be connected to the respective high-pressure pressure field of the pump; Thus it can be achieved that a pressure sensor too in an MPE with two flow directions, in particular a multi-quadrant MPE always recorded the current high pressure.

The fluid may be, for example, a hydraulic fluid, i. Act hydraulic oil.

The sensor receptacle is preferably an integral part of a structure forming the housing of the MPE. The sensor receptacle is preferably located in a region of the housing in which no functional parts of the MPE be. Thus, the space of the MPE is not significantly changed by the integration of the sensor, especially not enlarged.

Under "housing" is here first understood the part of the MPE, the functional components, such as. As the pump, the electric motor, the controller, the sensor, etc., the MPE protective "einhaust" and holds. The term "housing" in the context of the present invention is not limited to hen limited to the externally visible shell of the MPE. The term "housing" here explicitly also covers such structures lying inside the MPE, such as interior walls, struts, etc., as well as flange parts for connecting two functional units or two parts of a functional unit, which are integral with the MPE constituent parts of the MPE or are connected thereto and / or receive, envelope or at least hold functional elements of the functional units of the MPE. Therefore, the sensor according to the invention is integrated in the sensor receptacle as an integral part of the housing of the MPE in the housing of the MPE.

As already noted, the sensor is not visible from outside through its arrangement in the sensor receptacle in the housing of the MPE, in particular of not accessible on the outside. Thus, the sensor is protected by the housing of the MPE op timal against environmental influences.

The at least one sensor may be a pressure sensor which is integrated into the housing of the MPE for detecting the pressure in the fluid flowing through the pump at a pressure-side fluid connection of the pump or a suction-side fluid connection of the pump. If the pump is an internal gear pump, the pressure sensor for detecting the pressure in the fluid flowing through the pump at a pressure-side Axialdruckfeld the pump or a suction-side Axialdruckfeld the pump with the fluid, possibly via an auxiliary bore, in pressure sensor contact.

In a preferred embodiment, two pressure sensors are provided for pressure detection, in which case one is integrated into the housing of the MPE as internal gear pump in each case one at a pressure-side and at a suction-side hydraulic connection of the pump or in a Axialdruckfeld the pump. In any case, according to the invention, a sensor receptacle according to the invention is integrated in the housing of the MPE for the two pressure sensors.

If the MPE can deliver fluid in two directions, the two pressure sensors alternately sense the suction side or the pressure side pressure in the fluid. As already noted elsewhere, a pressure sensor can also be connected via a check valve interconnection with both fluid ports or an internal gear pump with the Axialdruckfeldern the pump, so that the pressure sensor is always connected to the high-pressure pressure field; Thus, the pressure sensor at the MPE always records the current high pressure.

The MPE may also be configured as multi-quadrant machines, that is, operable as a motor and generator.

Depending on the underlying physical principle, a pressure sensor may be a piezoresistive or piezoelectric pressure sensor, a Hall element, a capacitive or inductive pressure sensor.

The sensor receptacle can be configured in the housing so that a pressure-detecting surface of the pressure sensor can detect the pressure in the fluid at a fluid connection or optionally at an axial pressure field directly or via an auxiliary bore.

For pressure detection, the pressure sensor has a pressure sensing surface, with which the pressure sensor in the operation of the MPE with the flowing fluid through the pump with the fluid leading interior of the fluid ports of the MPE directly or via an auxiliary bore which connects the interior of the fluid port with the sensor receptacle, in contact.

The housing consists at least of a pump housing part, are included in the functional parts of the pump. The sensor receptacle is preferably a structural component of the pump housing part.

The housing of the MPE can consist of several housing parts, which together define the shell of the MPE. The housing parts are then next to the pump housing part for receiving the functional elements of the pump, a motor housing part for receiving the functional elements of the electric motor and a control housing for receiving the components of the controller.

The pump housing part, the motor housing part and the control housing part may each be in one or more parts.

The individual housing parts may have flanges for connecting two functional units or two housing parts of a functional unit. In example, the pump housing part can have a motor-side pump flange for connection to a motor housing in which the electric motor be found.

The pump housing part defines in its interior the space for receiving the functional parts of the pump for the promotion of the hydraulic fluid and for driving coupling with the electric motor.

The interior of the pump housing part may be closed on the motor-side pump flange axially opposite sides of the pump with a pump end ckel. Alternatively, the pump housing part may form one end of the housing of the MPE. Preferably, the pump housing part is then closed axially on the motor side with a pump-side motor flange of a motor housing.

For driving coupling with the electric motor, the pump may be connected, for example via a guided through the motor flange drive shaft with the electric motor.

The suction-side and the pressure-side fluid connection can each be located either on the pump housing part or on the pump cover. Preferably, the two fluid connections are located on the pump cover. In this case, the fluid connections can be embodied in the pump cover such that the sensor surface of the pressure sensor comes into direct contact with the fluid during operation of the MPE stands. Alternatively, an auxiliary bore may be provided in the pump cover, which establishes a communicating connection with the fluid between the interior of a fluid connection (or possibly an axial pressure field) and the sensor surface of the pressure sensor during operation of the MPE.

In a first variant, the sensor receptacle can extend orthogonally to a longitudinal axis of the MPE defined by the electric motor and the pump.

In this first variant of the sensor receptacle, the sensor receptacle can be integrated radially to the longitudinal axis of the MPE in the pump housing part or pump housing cover, for example as a blind hole, such that an open end of the sensor receptacle is closed by means of the control housing part of the control when the MPE is assembled. At the end opposite the open end, the sensor receptacle is connected directly or via the auxiliary bore to the interior of one of the fluid connections (or possibly an axial pressure field).

In the first variant, the control housing can be connected radially at least laterally with respect to the longitudinal axis of the MPE defined by the pump and the electric motor, at least with the pump housing part, and can also be connected to the motor housing part. For electrical connection of the electrical connections of the sensor to the controller, these may be in spring-loaded or mated contact directly or via connecting means located therebetween with contact points on a circuit of the controller.

In a second variant, the sensor receptacle can extend coaxially with the longitudinal axis defined by the electric motor and the pump through the pump housing part.

In this second variant, the sensor receptacle extends axially in, for example as a through hole, through the pump housing part. At a first open end, the sensor receptacle can then be closed by means of the pump cover. For sealing, a seal can be provided between the pump cover, the pump housing part and the sensor. Preferably, it may be an O-ring seal. Preferably, the sensor is inserted from the direction of the pump cover in the sensor receptacle so that its pressure-sensitive sensor surface is aligned in the direction of the pump cover.

The sensor and the sensor receptacle particularly preferably have positively cooperating elements, for example a projection on the sensor and an edge on the sensor receptacle, which are matched to one another in such a way that the sensor inserted in the sensor receptacle is fixed similarly to a cartridge in a cartridge chamber. In the case of the pressure sensor, the pressure sensor, in that the pressure sensor is acted upon during operation of the MPE with the pressure in the hydraulic fluid, additionally securely fixed in the sensor receptacle.

In an alternative embodiment or in addition to the above-described NEN embodiment, the sensor may also have an external thread and the sensor receptacle have a corresponding internal thread, so that the sensor can be screwed into the sensor receptacle.

For sealing, a seal, for example an O-ring seal, can be provided between the pump cover, the pump housing part and the sensor.

In the second variant, the second open end of the sensor receptacle may be superimposed with a through-hole in a pump-side motor flange in order to contact electrical connections of the sensor located on this side. If the pump housing part has a motor-side pump flange, the electrical connections of the sensor can already be contacted due to the sensor receptacle in the form of a through-hole. In this embodiment, the control housing of the controller is preferably axially connected to the motor housing at the pump housing opposite end of the motor housing via a control-side motor flange or a motor-side control housing flange.

For the electrical connection of the sensor to the control connecting means are still to be explained, which connect the electrical contacts of the sensor through the motor housing through with corresponding electrical contacts on a circuit of the controller in the control housing spring loaded or plugged electrically connected.

The controller is preferably configured for controlling (or regulating) the electric motor and for supplying the sensor with energy and for interrogating a sensor signal provided by the sensor, for example a pressure signal.

The MPE may have an electrical contact bridge for the sensor, wherein the contact bridge runs axially through the electric motor and connects electrical connections of the sensor and associated electrical connections of the controller.

In a preferred embodiment, the electrical contact bridge consists of dimensionally stable elements with integrated elements extending in the longitudinal direction of the MPE electrical conductors. The conductor tracks may be formed from contact sheets and molded or encapsulated with an electrically insulating plastic material.

Preferably, the conductor tracks are shaped so that the conductor tracks on the pump side form first contacts for the electrical connections of the sensor and control side second contacts for the electrical connections to the control. The conductor tracks may for example be L-shaped and have sensor-side corresponding contact surfaces for resilient contact pins on the associated sensor and control side corresponding plug contacts for a plug connection with a plug of the controller or arranged in a circuit board of the controller plug contact.

About the electrical contact bridges, d. H. the conductor tracks, the sensor is supplied by the controller with the necessary electrical power (ge fed) and the sensor signal generated by the sensor, led to the control or queried by this.

For example, a sensor may be a pressure sensor having three electrical contacts. Accordingly, a contact bridge then has three tracks. By means of the contact bridges, the electrical connection of the pressure sensor to the control unit within the motor housing and is thus protected against environmental influences and not visible from the outside. The electrical pressure signal generated at the measuring point, proportional to the pressure prevailing there in the fluid, is forwarded by the pressure sensor via the contact bridge to the control unit.

In a development of the MPE, the controller has a data interface to a communication bus, in particular a CAN bus or field bus or Like, on and is adapted to provide the sensor signal detected by the at least one sensor or a data signal corresponding to the sensor signal on the communication bus.

In particularly preferred embodiments of the MPE, at least two pressure sensors are integrated in the housing of the MPE, wherein a first pressure sensor for detecting the pressure in the fluid at a first fluid port of the pump and a second pressure sensor for detecting the pressure in the fluid at a second fluid port of the pump pressure sensor to be in contact with the fluid. As already described in other places, the pressure sensors can also be pressure-sensitive to corresponding axial pressure fields of the pump in contact with the fluid when the pump is an internal gear pump. If the MPE is a multi-quadrant machine, the two pressure sensors are alternately in pressure-sensing connection with the suction-side or the pressure-side fluid connection in accordance with the current delivery direction.

A second aspect of the invention relates to a fluid system which comprises fluid lines and an MPE connected to the fluid lines according to the first aspect of the invention with at least one integrated sensor in the form of a pressure sensor. The fluid may be, for example, a hydraulic fluid. Such a hydraulic system may for example be part of a motor vehicle, a work machine, etc.

• Zunächst ist eine Gefahr der Beschädigung eines nun nicht mehr extern angeordneten Drucksensors ausgeschlossen. Durch die robuste und geschützte Integration des Drucksensors in das Gehäuse der MPE ist dieser vor Korrosion und mechanischer Beschädigung geschützt. Damit ist besonders eine Verwendung von Sensoren ohne besondere mechanische Schutzmaßnahmen gegen Korrosion oder Beschädigung möglich.

An inventively improved MPE offers in the scenario described above with an MPE in a hydraulic system and separate Drucksenso ren for detecting the pressure in the hydraulic fluid numerous advantages:

• First, a risk of damage to a now no longer externally arranged pressure sensor is excluded. The robust and protected integration of the pressure sensor into the housing of the MPE protects it from corrosion and mechanical damage. This makes it possible to use sensors without special mechanical protective measures against corrosion or damage.

The assembly effort of an overall system is simplified in several ways: The pressure sensor or sensors no longer need to be mechanically adapted in the hydraulic system. Since the sensors can already be electrically tuned during integration into the MPE (eg offset correction), this is no longer necessary later in the overall system. There is no extra space for the pressure sensor necessary. The MPE is more compact and the packaging is better suited for use in motor vehicles. The expense of electrically connecting one or more pressure sensors in the system, e.g. Wiring installation etc. omitted. Since there is no longer any external connection of the pressure sensors, the usual potential errors in cable trees, such as cable breakage, tearing, corrosion of contact points are excluded. The elimination of the electrical connection reduces the installation effort accordingly. Since no pressure sensors need to be installed, interchanging electrical connections, e.g. due to miscarriage, excluded.

The control of the MPE has due to the integrated pressure sensor a "own" pressure signal, ie a feedback of the actual state variable, so that the controller can control the electric motor as the drive of the pump, for example, to avoid pressure pulsations in the hydraulic fluid. This eliminates the need for an additional pressure sensor in the system. The controller can via appropriate interfaces, such. B. to the CAN bus, the or the MPEintern detected (n) pressure signal (s) to other control devices communicate.

Since the pressure sensor and the MPE are virtually positively coupled by the integration of the pressure sensor into the MPE, both are tested together accordingly. In other words, during production and EOL testing of the MPE, it is already tested with the associated pressure sensors.

The above advantages, which have been explained with reference to a pressure sensor as an exemplary embodiment of a sensor integrated into the MPE, can also be realized correspondingly for other sensors.

Figur 1

eine schematische Schnittdarstellung der integralen Anordnung eines Drucksensors in einer MPE gemäß einer ersten Ausführung;

Figur 2

eine schematische Schnittdarstellung der integralen Anordnung eines Drucksensors in einer MPE gemäß einer alternativen Aus führung;

Figur 3

eine perspektivische Ansicht einer MPE gemäß der ersten Aus führung;

Figur 4

die perspektivische Ansicht der MPE der Figur 3 mit ausgeblendetem Pumpengehäuseteil;

Figur 5

die perspektivische Darstellung der MPE der Figur 4 mit weiter ausgeblendetem Motorgehäuseteil;

Figur 6

eine perspektivische Ansicht der MPE der Figuren 3-5 ohne elektronische Ansteuereinheit und ohne Motorgehäuse;

Figur 7

eine Schnittdarstellung der MPE der Figuren 3-6;

Figur 8

eine perspektivische Darstellung MPE der Figur 3 ohne elektronische Ansteuereinheit und damit Sicht auf die Schnittstelle zwischen Motoreinheit und elektronische Ansteuereinheit.

Further advantages, features and details of the invention will become apparent from the following description in which exemplary embodiments of the invention are described in detail with reference to the drawings. The features mentioned in the claims and in the description may each be essential to the invention individually or in any desired combination. Likewise, the features mentioned above and the features further explained herein can be used individually or in combination in any desired combination. Functionally similar or identical components or components are partially provided with the same reference numerals. The terms "left", "right", "top" and "bottom" used in the description of the embodiments refer to the drawings in an orientation with normally readable figure designation or normal readable reference numerals. The embodiment shown and described is not to be understood as exhaustive, but has exemplary character for explaining the invention. The detailed description is primarily for the information of the person skilled in the art, therefore, in the description of known circuits, structures and methods are not shown or explained in detail Understand the present description is not difficult. The invention will now be described by way of example with reference to the accompanying drawings. Show:

FIG. 1

a schematic sectional view of the integral arrangement of a pressure sensor in an MPE according to a first embodiment;

FIG. 2

a schematic sectional view of the integral arrangement of a pressure sensor in an MPE according to an alternative imple mentation;

FIG. 3

a perspective view of an MPE according to the first imple mentation;

FIG. 4

the perspective view of the MPE the FIG. 3 with hidden pump housing part;

FIG. 5

the perspective view of the MPE the FIG. 4 with further hidden motor housing part;

FIG. 6

a perspective view of the MPE of Figures 3-5 without electronic control unit and without motor housing;

FIG. 7

a sectional view of the MPE the Figures 3-6 ;

FIG. 8

a perspective view MPE the FIG. 3 without electronic control unit and thus view of the interface between motor unit and electronic control unit.

In the exemplary embodiments described below, the sensor integrated in an MPE is a pressure sensor. However, this should not be understood as a limitation of the here proposed integration of a sensor in an MPE on pressure sensors. Rather, other sensors in the manner proposed here can be advantageously integrated into an MPE.

The Figures 1 and 2 First, each show a schematic sectional view with an integral arrangement of a pressure sensor in an electro-hydraulic motor-pump unit, MPE 1, 2 according to a first and according to an alternative embodiment.

The MPE 1 of the FIG. 1 and the MPE 2 of the FIG. 2 consist essentially of three functional units: a pump unit 100 with a pump 10 for conveying a hydraulic fluid in a hydraulic system HS; a drive unit 200 coupled to the pump unit 100 for driving the pump 10 with an electric motor 20; and a control unit 300, which is coupled to the drive unit 200 and is designed to control or regulate the electric motor 20, having a controller 30.

The controller 30 is configured to control (or regulate) the electric motor 20 and to provide power to the pressure sensor 70 and to interrogate a pressure signal provided by the pressure sensor 70. Depending on the underlying physical principle, the pressure sensor 70 may be a piezoresistive or piezoelectric pressure sensor, a Hall element, a capacitive or inductive pressure sensor; In principle, other physical principles not mentioned here or future for pressure measurement for a sensor to be integrated in the MPE are also conceivable.

The pump 10, the electric motor 20 and the controller 30 are enclosed by a housing 50 of the respective MPE 1, 2. As already explained, the term "housing 50" is understood to mean that part of the MPE 1, 2 which protects, surrounds and holds the pump 10, the electric motor 20, the controller 30, etc. of the MPE 1, 2. The feature "housing 50" is not in the context of the present invention as visible to the outside Cover the MPE 1, 2 limited to understand. The feature "housing 50" also encompasses internal structures of the MPE 1, 2 which are integral with or connected to the components forming the envelope of the MPE. Structures lying inside the MPE 1, 2 can be, for example, interior walls, struts, etc., but also flange parts for connecting two functional units or two parts of a multi-part functional unit. In other words, the housing 50 is formed by those parts of the MPE 1, 2 which receive, encase or at least hold functional elements of the functional units 100, 200, 300 of the MPE.

The housing 50 of the MPE 1, 2 consists of a plurality of housing parts 51, 52, 53, which together form the housing 50 of the MPE 1, 2. In the variants of Figures 1 and 2 the housing parts are a pump housing 51 for receiving the functional components of the pump 10, a motor housing 52 for receiving the functional components of the electric motor 20 and a control housing 53 for receiving the components of the controller 30.

In principle, at least one housing part (pump housing 51, the motor housing 52 and the control housing 53) can be in one piece or in several parts. In the remarks of the Figures 1 and 2 the pump housing 51 is made in two parts and has a housing cover 51 a and a pump housing part 51 b.

It should be noted that the pump housing 51 may have only the pump housing part 51 b, which then forms one end of the housing 50 of the MPE 1, 2. In this case, the pump housing part 51 b may then be axially closed on the motor side with a pump-side motor flange of the motor housing 52.

The pump housing part 51 b defines in its interior the space for the acquisition of the functional parts of the pump 10 for the promotion of the hydraulic fluid and for driving coupling with the electric motor 20. The pump 10 is coupled via a guided through an engine-side pump flange drive shaft W to the electric motor 20 ,

In both embodiments, at least one pressure sensor 70 is integrated into the housing 50 of the MPE 1, 2, in that the pressure sensor 70 is arranged in a sensor receptacle 80 integrated into the housing 50. As a result, the pressure sensor 70 is inaccessible to the outside through the housing 50 when the MPE 1, 2 are mounted and thus shielded from environmental influences. The sensor receptacle 80 is an integral part of the housing 50 of the MPE 1, 2. Thus, the pressure sensor 70 located in the sensor receptacle 80 is integrated into the housing 50 of the MPE 1, 2.

In the execution of FIG. 1 For example, the pressure sensor 70 is electrically connected to the controller 30 via a contact bridge 90 through the motor unit 200. In the execution of FIG. 2 For example, the pressure sensor 70 is electrically connected directly to the controller 30 disposed adjacent to the pressure sensor 70.

The pressure sensor 70 located in the sensor receptacle 80 is in pressure-sensory contact with the hydraulic fluid delivered by the pump 10 during operation of the MPE 1, 2 by means of the pump 10 at a hydraulic connection 41 of the MPE 1, 2 in order to detect the hydraulic pressure present there in the hydraulic fluid. For pressure detection, the pressure sensor 70 has a pressure sensing surface 73, via which the pressure sensor 70 in the operation of the MPE 1, 2 with the hydraulic fluid flowing through the pump 10 with the interior of the hydraulic connections 40 of the MPE 1, 2 leading the hydraulic fluid via an auxiliary bore 85, which connects the interior of the hydraulic connection 41 with the Sensorauf acquisition 80, is in contact.

Between the pump cover 51 a and pump housing part 51 b or, if the pump housing consists only of the pump housing part 51 b, between the pump housing part 51 b and the pressure sensor 70 is in the FIG. 1 not shown seal arranged to seal the sensor receptacle 80 against the hydraulic fluid.

Alternatively, when the pump 10 is a positive displacement pump in the form of an internal gear pump, the pressure sensor 70 may be in pressure sensing contact directly or via an auxiliary bore with an axial pressure field of the pump.

In the schematic sectional view of FIG. 1 For example, an MPE integral arrangement of a pressure sensor 70 according to the first embodiment is shown. The sensor receptacle 80 extends coaxially with a longitudinal axis LA of the MPE 1 defined by the electric motor 20 and the pump 10 through the pump housing part 51b. The sensor receptacle 80 extends axially as a through hole through the pump housing part 51 b and is thus integrated into the pump housing part 51 b.

At a first open end 81, the sensor receptacle 80 is closed by means of the pump cover 51 a. The pressure sensor 70 is inserted from the direction of the pump cover 51 a in the sensor receptacle 80 much like a cartridge in a cartridge chamber so that its pressure-sensitive sensor surface 73 is aligned in the direction of the pump cover 51 a. Alternatively, the pressure sensor 70 may also be screwed via corresponding threads on the sensor and the sensor receptacle in the pump housing part 51 b. At the pump cover 51 a are two hydraulic ports 41, 42 of the pump 10. In the pump cover 51 a, an auxiliary bore 85 is provided, via which a pressure sensor contact is made between a sensor surface of the pressure sensor 70 during operation of the MPE 1 with the hydraulic fluid at the hydraulic port 41.

A second open end 82 of the sensor receptacle 80 may be superposed with a through hole in a pump-side motor flange to contact located on this side electrical connections of the pressure sensor 70. If the pump housing part 51 b has a motor-side pump flange, the electrical connections of the pressure sensor 70 can already be contacted due to the sensor receptacle 80 in the form of the through-hole.

In the execution of the FIG. 1 the control housing 53 of the control unit 300 is preferably axially connected to the motor housing 52 at the pump unit 100 opposite end of the motor housing 52 via a control-side motor flange or a motor-side control housing flange.

For the electrical connection of the pressure sensor 70 with the controller 30 contact bridges 90 are provided as connecting means which establish an electrical connection through the motor housing 52 between electrical contacts of the pressure sensor 70 and corresponding electrical contacts on a circuit board 31 of the controller 30 in the control housing 53.

In the schematic sectional view of FIG. 2 is an MPE integral arrangement of a pressure sensor 70 according to an alternative embodiment ge shows. In this case, the sensor receptacle 80 is orthogonal to that through the Electric motor 20 and the pump 10 defined longitudinal axis LA of the MPE 2 in the pump housing part 51 b.

The sensor receptacle 80 is radially integrated with the longitudinal axis of the MPE 2 in the pump housing part 51 b as a blind hole so that an open end 82 of the sensor receptacle 80 is closed by means of the control housing part 53 of the controller 30 with assembled MPE 2. At the end 81 opposite the open end 82, the sensor receptacle 80 is connected to the interior of the hydraulic connection 41 via the auxiliary bore 85. Again, the pressure sensor 70 may be screwed via corresponding threads on the sensor 70 and the Seinsoraufnahme 80 in the pump housing part 51 b.

Also in this embodiment is to seal the sensor receptacle 80 between the pressure sensor 70 and the pump housing part 51 b in the FIG. 2 not shown seal arranged to seal the sensor receptacle 80 against the hydraulic fluid.

Also in this embodiment, when the pump 10 is a positive displacement pump in the form of an internal gear pump, the pressure sensor 70 may alternatively be in pressure sensing contact directly or via an auxiliary bore with an axial pressure field of the pump.

In this embodiment, the control housing 53 is connected radially laterally at least to the pump housing part 51 b and to the motor housing part 52 with respect to the longitudinal axis LA of the MPE 2 defined by the pump 10 and the electric motor 20.

For the functional electrical connection of the electrical connections of the pressure sensor 70 with the controller 30, these can in the second embodiment are directly or also via intermediate connecting means with contact points on a circuit board of the controller 30 in a preferably spring-loaded or plugged electrical contact.

The following is with reference to the FIGS. 3 to 8 a preferred embodiment of an MPE 1 explained in detail, which essentially corresponds to the embodiment in the FIG. 1 equivalent.

FIG. 3 11 shows a perspective view of the MPE 1. The MPE 1 is composed of the pump unit 100 having a pump 10 for supplying a hydraulic fluid in a hydraulic system, a motor unit 200 coupled to the pump unit 100 for driving the pump 10, and a driver coupled to the motor unit 200 for driving All functional units are enveloped by a housing 50 of the MPE 1.

The housing 50 is formed of a plurality of housing parts, namely the pump housing 51, the motor housing 52 and the control housing 53. The pump housing 51 is made in two parts and consists of a pump cover 51 a and a pump housing part 51 b. At the pump cover 51 a are two hydraulic ports 41, 42 of the pump unit 100th

FIG. 4 shows the perspective view of the MPE 1 of FIG. 3 with hidden pump housing part 51 b. In the FIG. 4 are now compared to FIG. 3 the two pressure sensors 71, 72 arranged in the housing 50, namely in the pump housing part 51b, and shielded from the outside by the housing 50 and electrically connected to the control unit 300. By the suppression of the pump housing part 51 b is clearly visible that the pump housing part 51 b forms in its interior the space for receiving the functional parts of the pump 10 for the promotion of the hydraulic fluid and for driving coupling with the electric motor 20.

The pump is designed as an internal gear pump, so are in the pump housing part 51 b arranged substantially: a driven pinion with external teeth, a toothed with the pinion gear ring with internal teeth and a housing-integrated, crescent-shaped filler, which is symmetrical to a median plane between the pinion and the ring gear is formed and forms with the teeth of the pinion and the ring gear tooth chambers.

The pump 10 is coupled via a through the motor-side pump flange 51 c (Figure 6) guided drive shaft to the electric motor 20 for driving the pinion of the pump 10.

For axial sealing is between the gears and the pump housing portion 51 b on one side and the pump cover 51 a on the other side (not shown) each arranged an axial pressure plate, each of a between the Axialdruckplatte and the pump housing part 51 b or pump cover 51 a generated Axialdruckfeldes axially against pinion and gear ring is pressed. The Axialdruckplatten have holes which are penetrated by a drive shaft for the pinion, and are thereby arranged in a plane perpendicular to the axes of the gears. An axial pressure field is formed either in a recess in the pump housing part 51 b or pump cover 51 a or housing side in the respective thrust plate and compared to the (not shown) sickle semi-sickle-shaped, so that the Axialdruckfeld extends only on one side of the median plane of the sickle.

Each Axialdruckfeld is connected, for example via a bore in the Axialdruckplatte depending on the conveying direction of the pump with the suction chamber or pressure chamber of the pump 10. There is no connection between the two Axialdruckfeldern on a thrust plate, d. h., Depending on the conveying direction of the pump, the high pressure generated by the pump is built in a Axialdruckfeld the Axialdruckplatten and in the other Axialdruckfeld the suction pressure.

In the case of the pump 10 in the form of an internal gear pump, the pressure sensors 71, 72 are each in pressure-sensory contact with the delivered hydraulic fluid at one of the two pump housing-part-side axial pressure fields of the pump. The pressure detected at the respective axial pressure field corresponds respectively to the suction-side or the pressure-side pressure in the hydraulic fluid. Thus, in the exemplary embodiment shown here, two pressure sensors 71, 72 are integrated into the housing 50 of the MPE 1. A first one of the pressure sensors 71 is arranged to detect the pressure in the hydraulic fluid at a first 41 of the hydraulic connections 40 and a second pressure sensor 72 to detect the pressure in the hydraulic fluid at a second 42 of the hydraulic connections 40. The MPE 1 is designed as a multi-quadrant machine and accordingly, the pressure sensors 71, 72 respectively detect the suction-side or the pressure-side hydraulic pressure according to a current flow direction of the hydraulic fluid.

FIG. 5 shows the perspective view of the MPE 1 of Figures 3 and 4 , in comparison to FIG. 4 in addition, the motor housing part 52 is hidden. Here it can be clearly seen that the interior of the pump housing part 51 b on the motor-side pump flange 51 c ( FIG. 6 ) axially opposite sides of the pump unit 100 with the pump cover 51 a is closed.

FIG. 6 shows a perspective view of the electro-hydraulic motor-pump unit (MPE) of Figures 3-5 without control unit 300 and without motor housing 52. In the FIG. 6 is in addition to the representations of FIGS. 3 to 5 It can be clearly seen that the pump housing part 51 b has a motor-side pump flange 51 c for connection to the motor housing 52, in which the electric motor 20 is located.

The Figures 5 and 6 The contact bridges 91, 92 extend axially through the motor unit 200 and connect electrical connections 74 ', 75' of the pressure sensor 70 and associated electrical connections 32 of the controller 30.

The electrical contact bridges 91, 92 are elongated dimensionally stable elements with integrated electrical conductors 93. The conductors 93 are each Weil punched out of contact plate, then formed, and then encapsulated or encapsulated with an electrically insulating plastic material.

The printed conductors 93 have been converted into an L shape in the embodiment shown, so that the printed conductors 93 on the pump side have first contacts 93a ', 93b', 93c 'for associated electrical connections 73', 74 ', 75', 73 ", 74", 75 ". one of the pressure sensors 71, 72 and control side second contacts 93a ", 93b", 93c "for electrical connections 32 on the controller 30 have.

By means of the electrical contact bridges 91, 92, ie the respective conductor tracks 93, the pressure sensors 71, 72 are fed by the controller 30 with the necessary electrical power and that of the respective pressure sensor 71, 72 queried at its associated hydraulic port 41, 42 proportional to the prevailing pressure generated electrical pressure signal from the controller 30.

Characterized in that the electrical connection of the pressure sensors 71, 72 to the controller 30 through and thus within the motor housing 52, the electrical connection of the pressure sensors 71, 72 as the Drucksenso ren 71, 72 itself protected by the housing 50 against environmental influences and also not visible from the outside.

FIG. 7 shows a sectional view through the MPE of Figures 3-6 , It can be clearly seen in FIG. 7 that the housing 50 of the MPE 1 has the pump housing part 51 b, in which functional parts of the pump 10 are held and enclosed, and in particular that the sensor receptacle 80 is a structural component of the pump housing part 51 b. The sensor receptacle 80 extends coaxially with the longitudinal axis LA defined by the motor unit 200 and the pump unit 100 as a through-hole through the pump housing part 51 b.

The pressure sensor 70 communicates with the hydraulic fluid delivered during operation of the MPE 1 at one of the hydraulic connections 41, 42 of the MPE 1 via an in FIG. 7 Not shown auxiliary bore in pressure-sensitive contact. The sensor receptacle 80 is configured in the pump housing part 51 b such that a pressure-detecting surface of the pressure sensor 70 can detect the pressure in the hydraulic fluid at one of the hydraulic connections 41, 42 via the auxiliary bore (not shown).

At a first open end 81, the sensor receptacle 80 is closed by means of the pump cover 51 a. The pressure sensor 70 is out of the direction of Pump cover 51 a inserted into the sensor receptacle 80 so that its pressure-sensitive sensor surface 73 is aligned in the direction of the pump cover 51 b.

The pressure sensor 70 and the sensor receptacle 80 have positively cooperating elements, for example a circumferential projection on the pressure sensor 70 and a corresponding peripheral edge on the sensor receptacle 80. The projection and edge are matched to one another such that the pressure sensor 70 inserted in the sensor receptacle 80 is similar to a Cartridge is set in a chamber. To seal the Sensorauf acceptance 80 relative to the hydraulic fluid is in the FIG. 7 not shown in detail O-ring seal provided.

The hydraulic connections 40 and the sensor receptacle 80 can be designed such that the sensor surface 73 of the pressure sensor 70 is in direct contact with the hydraulic fluid at the associated hydraulic connection 40 during operation of the MPE 1. In the embodiment of FIGS. 3 to 8 is in the pump end ckel one in the FIG. 7 Auxiliary bore, not shown, via which the sensor surface 73 of the pressure sensor 70 is in contact with the hydraulic fluid at the associated hydraulic port 40 during operation of the MPE 1. Due to the fact that the pressure sensor 70 is loaded with the pressure in the hydraulic fluid during operation of the MPE 1, the pressure sensor 70 is additionally securely fixed in the sensor receptacle 80.

Characterized in that in this embodiment, the pump housing part 51 a the motor-side pump flange 51 c, the electrical connections of the pressure sensor 70 through the contact bridges 91, 92 are contacted due to the Sensorauf exception 80 in the form of the through hole. alternative For example, the second open end 82 of the sensor receptacle 80 could be brought into coincidence with a through hole in a pump-side motor flange, so that the electrical connections of the pressure sensor 70 located on this side can be contacted again by means of the contact bridges 91, 92.

The control housing 53 of the control unit 300 with the control 30 is axially connected to the motor housing 52 at the end of the motor housing 52 opposite the pump unit 100 via a control-side motor flange 52 c (FIG. FIG. 8 ) connected. Alternatively, the connection could also be made via a motor-side control housing flange.

FIG. 8 shows a perspective view of FIG. 3 without electronic control unit and view of the interface between motor unit and electronic control unit. In addition to the already explained housing parts pump cover 51 a, pump housing part 51 b, motor housing part 52 is in the FIG. 8 by the suppression of the control unit 300 to recognize the good control side motor housing flange 52c. In the motor housing flange 52c there are first through holes through which electrical terminals 21, 22, 23 of the windings of the electric motor 20 are guided, and second through holes through which the control side second contacts 93a ", 93b", 93c "of the contact bridges for electrical terminals 32 abut the controller 30.

Finally, it should be noted that the control unit 300 has a data interface, not shown in the figures, for connection to a communication bus, for example a CAN bus or field bus or the like, and is set up alongside other communication purposes the two pressure sensors 71, 72 to provide detected hydraulic pressures on the communication bus.

Claims (17)

Electrohydraulic motor-pump unit (1), MPE, with a pump (10) for conveying a fluid, an electric motor (20) coupled to the pump (10) for driving, one coupled to the electric motor (20) and for driving the Electric motor (20) equipped control (30) and a housing (50),
characterized by at least one sensor (70, 71, 72) arranged in a sensor receptacle (80) integrated in the housing (50) and electrically connected to the control (30). The MPE (1) of claim 1, wherein the at least one sensor (70, 71, 72) is shielded outwardly through the housing (50). MPE (1) according to claim 1 or 2, wherein at least one sensor (70, 71, 72) is a pressure sensor (70, 71, 72) which communicates with the fluid conveyed during operation of the MPE (1) at a fluid connection (40, 41, 42) of the MPE (1) is in pressure-sensoric contact. MPE (1) according to one of claims 1 to 3, wherein the pump (10) is an internal gear pump and at least one sensor (70, 71, 72) is a pressure sensor (70, 71, 72), wherein the at least one pressure sensor (70 , 71, 72) is in pressure-axial contact with the fluid in an axial pressure field of the pump (10). MPE (1) according to claim 3 or 4, wherein the sensor receptacle (80) in the housing (50) is configured so that a pressure sensing surface of the pressure sensors (70, 71, 72) can detect the pressure in the fluid directly or via an auxiliary bore (85). MPE (1) according to one of claims 1 to 5, wherein the housing (50) has a pump housing part (51 b) are received in the functional parts of the pump (10), and wherein the sensor receptacle (80) is a structural part of the pump housing part ( 51 b). MPE (1) according to claim 6, wherein the pump housing part (51 b) has a motor-side pump flange (51 c) for connection to a motor housing (52) in which the electric motor (20) is located. MPE (1) according to claim 7, wherein the interior of the pump housing part (51 b) on the motor-side pump flange (51 c) axially opposite side of the pump (10) with a pump cover (51 a) is closed. MPE (1) according to claim 6, wherein the pump housing part (51 b) forms one end of the housing (50) of the MPE (1), and wherein the pump housing part (51 b) on the motor side with a pump-side motor flange of a motor housing (52) is axially closed , MPE (1) according to any one of claims 7 to 9, wherein as far back referring to claim 7 or 8, a suction-side and a pressure-side fluid port (40, 41, 42) either on the pump housing part (51 b) or the pump cover (51 a) are located , And being as far back related to claim 9, the suction side and the pressure side fluid port (40, 41, 42) on the pump housing part (51 b) are located. MPE (1) according to one of claims 1 to 10, wherein the sensor receptacle (80) is orthogonal to a longitudinal axis of the MPE (1) defined by the electric motor (20) and the pump (10). MPE (1) according to one of claims 1 to 10, wherein the sensor receptacle (80) coaxial with a by the electric motor (20) and the pump (10) defined longitudinal axis (LA) through the pump housing part (51 b) extends. MPE (1) according to one of claims 1 to 12, wherein the MPE (1) for the pressure sensor (70, 71, 72) has an electrical contact bridge (90, 91, 92), wherein the contact bridge (90, 91, 92) extends axially through the electric motor (20) and electrical connections (73 ', 74', 75 ', 73 ", 74", 75 ") of the pressure sensor (70, 71, 72) and associated electrical connections of the controller (30) connects. MPE (1) according to claim 13, wherein the electrical contact bridge (90, 91, 92) in the longitudinal direction of the MPE (1) extending dimensionally stable elements with integrated electrical conductor tracks (93), in particular Kontaktble surface, is formed, which with an electrically insulating Plastic material encapsulated or encapsulated and so, preferably L-shaped, are formed, that the conductor tracks (93) pump side first contacts (94, 94a ', 94b', 94c ') for, preferably resilient, electrical connections (73', 74 ' , 75 ', 73 ", 74", 75 ") of the pressure sensor (70, 71, 72) and control side second contacts (95, 95a", 95b ", 95c") for the electrical connections (32, 32a, 32b, 32c ) on the controller (30). MPE (1) according to one of claims 1 to 14, wherein the controller (30) has a data interface to a communication bus, in particular a CAN bus or field bus or the like, and is arranged, the provided by the at least one pressure sensor (70, 71, 72) detected fluid pressure on the communication bus. MPE (1) according to one of claims 1 to 15, wherein at least two pressure sensors (70, 71, 72) in the housing (50) of the MPE (1) are integrated, wherein a first pressure sensor (70, 71, 72) for detecting the pressure in the fluid at a first fluid port (40, 41, 42) of the pump (10) and a second pressure sensor (70, 71, 72) for detecting the pressure in the fluid at a second fluid port (40, 41, 42) of the pump (10) if the MPE (1) is a multi-quadrant machine, correspondingly changing, in pressure sensory Ver connection. Hydraulic system (HS), comprising hydraulic lines (HL) and an MPE (1) connected to the hydraulic lines (HL) according to one of claims 1 to 16 with at least one integrated pressure sensor.

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