WO2020089011A1

WO2020089011A1 - Housing cover for an electrical machine and method for producing a housing cover

Info

Publication number: WO2020089011A1
Application number: PCT/EP2019/078871
Authority: WO
Inventors: Ralph Guehrer; Manfred Zimmer; Sebastian Baumgart; Christian Brückner
Original assignee: Zf Friedrichshafen Ag
Priority date: 2018-10-30
Filing date: 2019-10-23
Publication date: 2020-05-07
Also published as: DE102018218527A1

Abstract

The present invention relates to a housing cover (10) for an electrical machine (30). The housing cover comprises a stator (11) of a rotor position sensor, which stator is integrated into the housing cover (10), for detecting an angular position of a rotor (33) of the electrical machine (30) and comprises an electrical plug-in connection (14) which is integrated into the housing cover (10). The plug-in connection (14) is designed in order to allow electrical contact to be made with the stator (11) on the housing cover (10) by means of plug-in contact. The invention further provides a method for producing a housing cover (10). The method comprises producing a first housing section (13a) of the housing cover (10) and also a second housing section (13b) which has a plug-in connection (14).

Description

Housing cover for an electrical machine and

Method of manufacturing a housing cover

The present invention relates to a housing cover for an electrical machine with a stator of a rotor position sensor integrated in the housing cover and a method for producing such a housing cover.

A rotor position sensor serves as an electromagnetic transmitter for converting an angular position of a rotor into an electrical variable. For example, stator windings of the rotor position sensor are arranged in a cylindrical housing of a rotor position sensor. An angular position of the rotor, which is accommodated in the housing, can be determined by evaluating voltage signals on the stator windings.

A motor with a rotor and a rotor control is known from JP 2009 126 189 (A). The rotor is covered by a cover that is screwed to the housing.

From DE 10 2015 217 875 a drive system with an electrical machine and a transmission is known, wherein a transmitter of the electrical machine is arranged on a drive side of the electrical machine. The encoder has an encoder stator and an encoder rotor, which are concealed in a gear housing. The encoder stator can be electrically contacted using an additional contact element.

Covering the assembled stator of the rotor position sensor by means of a closed cover can make it difficult to contact electrical connections of the stator. For example, the cover for contacting the electrical connections must be removed from the machine housing and individual cables connected to the connections individually. Contacting the stator connections via an intermediate contact element can be cost-intensive and require high accuracy, which can make contacting difficult. The object of the invention is therefore to provide a concept which simplifies contacting electrical connections of a stator of a rotor position sensor which is concealed in an assembled state.

Accordingly, a housing cover for an electrical machine, in particular an electrical machine of a motor vehicle, is provided. The housing cover comprises a stator of a rotor position sensor integrated in the housing cover for detecting an angular position of a rotor of the electrical machine. The cover according to the invention for the machine housing further comprises an electrical plug connector or an electrical plug contact element integrated in the housing cover.

The plug connection is designed to enable electrical contacting of the stator on the housing cover by means of a plug contact.

For this purpose, the plug connection can provide a plug receptacle or socket, the electrical contacts of which are each connected to connections of the stator. The connection can be realized by means of electrical conductors integrated in the housing cover, which are guided through a housing or on the housing of the housing cover, so that the mounted housing cover can cover, for example, the rotor and the stator of the rotor position sensor and thereby enable an external connection possibility to the stator of the rotor position sensor .

The housing cover has, for example, an opening on a front for receiving a rotor of the electrical machine. The back of the cover, on the other hand, can be closed, so that the rotor is completely enclosed when the housing cover is installed and is sealed by the housing cover. The plug connection can be provided on the back of the housing cover, so that it is accessible even when the housing cover is installed and the stator of the rotor position sensor can be easily contacted.

The integrated housing cover offers the advantage of simultaneously allowing hermetic closure of the rotor position sensor and electrical contacting of the stator connections. The rotor and stator can be covered, for example, oil-tight. - for example, the housing cover can be adapted to different rotor position sensor stators and / or plug contacts by different designs of the plug connection and can thus be used in a variety of ways. The plug connection allows a quick and easy contact of the stator for rotor position measurement with a reliable connection.

According to one embodiment of the housing cover, electrical contacts of the integrated plug connection are formed by electrical conductors integrated in the housing cover, which are electrically connected to the respective electrical connections of the stator. The electrical conductors extend from the stator to the plug connection. Electrical contact surfaces of the integrated plug contact element and / or the electrical conductor's, which lead through the housing cover or a housing part of the stator device provided to at least one stator winding of the stator, are electrically connected to the stator winding.

A number of electrical conductors integrated in the housing cover is selected depending on the number of stator windings present. With three stator windings, for example six electrical conductors can be guided in the housing to the plug connection. The shape of the plug connection can be adapted according to the number of existing electrical conductors and / or a predetermined plug shape of a plug that is to be used with the plug connection.

For example, an integrated electrical conductor comprises a lead frame. The advantage of using leadframes can be simple manufacture, low costs and / or dimensional stability when producing the housing cover by overmolding the leadframes in an injection molding process. The integrated electrical conductors can each comprise a metal strip and be arranged next to one another. The lead frame can be bent, for example, so that the plug connection can be provided in different positions or with different orientations in the housing cover. Alternatively or additionally, the electrical conductors can comprise cables or other electrically conductive structures. For example, an electrical connection of a respective electrical conductor is carried out on a respective electrical connection of the stator by means of a welded connection or a soldered connection. Alternatively or additionally, electrical contacting of a respective electrical conductor can be carried out on a respective electrical connection by means of a plug connection or clamp connection. For example, the electrical conductors can be contacted with the stator windings by means of insulation displacement terminals. The type of contacting of the electrical conductors with the connections of the stator can depend on the type of connections provided by the stator and can be selected individually.

According to one embodiment of the housing cover, electrical contacts of the integrated electrical plug connection are formed by respective electrical connections of the stator, which are guided in and / or on the housing cover from the stator to the plug connection. For example, the end regions of the stator windings that are led out of the stator can be integrated molded in the housing. The advantage here is that contacting the stator connections with additional electrical conductors can be dispensed with and the stator connections can serve directly as electrical contacts in the plug connection provided.

For example, the housing cover has a first side, e.g. the front, an opening for receiving the rotor and is arranged on a second side, which is remote from the first side, e.g. the back, closed design. The plug connection is e.g. formed on the second side of the housing cover. This makes the plug-in connection in the assembled state, with the front facing the machine housing, particularly easy to reach.

In a further development of the housing cover, the stator protrudes axially out of a housing part of the housing cover on one side of the housing cover, on which the opening for receiving the rotor of the electrical machine is formed in the housing cover. This results in an axial protrusion of the housing cover, through which the housing is formed sedeckel, to effect self-centering of the stator around the rotor when mounted on an axial recess of a machine housing of the electrical machine, which is complementary to the axial protrusion. A centering of the In other words, the stator around the rotor can be described by a coaxial arrangement of the stator and the rotor or by collinearly arranged axes of symmetry or rotation of the stator and the rotor.

For example, the axial projection is formed by a stator lamination stack of the stator or its housing protruding from the housing of the housing cover.

The axial protrusion is attached to an axial recess formed around a rotor of the electrical machine on a housing end face of the electrical machine, e.g. at least partially adapted positively. The axial protrusion can, for example, in addition to centering the stator also cause a predetermined angular position of the stator relative to the housing of the electrical machine due to a shape in a circumferential section.

The present invention thus provides a cover with an integrated electrical interface or plug or plug connection for a rotor position sensor e.g. ready for an electrical machine. This can be inexpensive and easy to use. The cover or housing cover is used to attach the stator of the rotor position sensor to a housing e.g. an electrically driven axis is provided.

The invention provides a method for producing a housing cover for a machine housing of an electrical machine. The method comprises producing a first housing section for receiving a stator of a rotor position sensor and producing a second housing section by overmolding to at least one electrical conductor in an injection molding process. According to the method, the first and second housing sections are arranged such that a first end of the at least one electrical conductor for contacting the stator protrudes from the first housing section into the second housing section and a second end of the at least one electrical conductor is an electrical contact from outside the Housing cover accessible plug connection for external contact animals of the stator by means of plug contact forms.

The method can be carried out in two stages, with the first housing section first or the connector housing by the extrusion coating of the electrical conductors, for example the lead frame is manufactured. The second housing section or the stator housing of the rotor position sensor or housing cover can then be injection molded onto the plug housing. For example, the stator is then attached to the stator housing and the stator connections are contacted.

According to one embodiment of the method, the first housing section and the second housing section are produced in a common injection molding process. The advantage can be a shorter manufacturing time and / or a more stable housing cover. The common injection molding process is a one-piece design of the integrated cover or housing cover. The electrical conductors, e.g. Punched grids can be inserted into a mold and overmolded, the housing part for receiving the stator of the housing cover being formed at the same time.

The integral cover formed according to the method has e.g. overmolded lead frames, which can be contacted on the one hand with further supply connections and on the other hand with the stator connections. The stator-side connection points of the lead frames protrude in the axial direction from the second housing section and into the first housing section in order to be contacted with the stator connections. The stator of the rotor position sensor can be attached to the stator housing or integrated cover via a press fit or press fit before or after contacting. The stator connections and the lead frames can generally be contacted by means of insulation displacement terminals or by means of a welded connection.

A production with a common overmolding process can also take place in that not only the lead frame, but also the stator (or the stator laminated core) is accommodated in the tool, and not only the cover with integrated lead frame is formed during the overmolding process, but also the stator is overmolded. The contacting of the stator connections and the lead frame can in turn take place before or after the overmolding process. For example, this enables a particularly stable connection of the stator to the stator housing.

In other words, the method can be used to form a cover with an integrated lead frame, the lead frame for direct contacting with the stator Conclusions are provided. For implementation, it is proposed, for example, to integrally form the lead frame and the stator housing or the housing part of the housing cover in which the stator of the rotor position sensor is accommodated. About the procedurally formed cover, the rotor position sensor or its stator can be attached directly to a housing, for example an electrically driven axis.

The invention further relates to an electrical machine with a rotor position sensor, which comprises a housing cover according to the invention, in which a stator of the rotor position sensor is provided. An oil-tight feed-through between the plug connection of the housing cover (e.g. a lead frame) and the cover is ensured by overmolding the plug connection or electrical conductor. The rotor of the machine can thus be hermetically sealed and the stator of the rotor position sensor can nevertheless be simply electrically contacted. The electric machine can be provided in a drive system of an electric motor vehicle.

Further developments of the method relate to features of further developments as already described in connection with the housing cover. A repeated description is therefore omitted and the corresponding features are also considered to be disclosed in connection with the method.

Some examples of devices are explained below with reference to the enclosed figures only by way of example. Show it:

Fig. 1 a, b an embodiment of a housing cover with integrated plug connection and contacting by means of insulation displacement devices;

Fig. 2a, b an embodiment of a housing cover with an integrated plug connection and a contact by means of a welded connection;

Fig. 3 shows a schematic section of an electrical machine with a mounted housing cover. 1 a shows an exemplary embodiment of a housing cover 10 or integrated cover with a stator 11 and an integrated plug connection 14 in a perspective view. The stator 1 1 of a rotor position sensor is at least partially accommodated in a housing 13 of the housing cover 10. The stator 11 is a first housing section 13a, for example a stator housing, which is formed adjacent to a second housing section 13b, for example a connector housing, in which the integrated connector 14 is provided. Electrical connections of the stator 1 1 are electrically connected to external connections at a contact point 12.

The first housing section 13a has, as fastening means, four recesses arranged around the stator for receiving screws, which enable screwing to a housing of an electrically driven axle or another component. On the first housing section 13a, a groove is also formed around the stator 11, in which a seal 21 is received. By means of the seal 21, a connection of the housing cover to a housing e.g. an electrically driven axis, e.g. oil-tight.

1 b shows the housing cover from FIG. 1 a in a schematic side view. The plug connector 14 is shown in more detail. The plug connection 14 has electrical contacts 15 which are contacted with stator connections 17 via electrical conductors 16. The stator connections 17 are e.g. provides at the contact point 12. The plug connection 14 can be designed as a socket that can accommodate a plug. An output of the socket has e.g. with respect to an axis of the stator radially inwards, so that a plug can be inserted to save space. The plug can be secured in the inserted state by means of a screw fastening and / or a clamp fastening 14a of the plug connection 14.

The example from FIG. 1 a, b shows contacting of the rotor position sensor stator 11 via its connections 17 with the electrical conductor 16 and the plug or plug connection 14 by means of a clamp connection 18, for example using insulation displacement terminals. The electrical conductors can be overmolded insulated cables which are inserted into insulation-piercing terminals of the stator at a first conductor end 16a in the stator housing. are clamped and are stripped at a second conductor end 16b in the plug connection in order to provide the electrical contacts 15 of the plug connection 14.

Fig. 2a shows an embodiment of a housing cover 10 with integrated plug connection 14 and an alternative contacting of the stator connections 17 with the electrical conductor, which is designed as a lead frame 16c, by means of a welded joint 19 in perspective view. The stator connections 17 can be designed as metal pins or metal conductor pieces on the stator 11 located radially outside. The electrical conductor or lead frame 16c are welded to the stator connections at the first conductor end 16a.

Fig. 2b shows the housing cover from Fig. 2a in a schematic side view. It can be seen that the electrical conductor 16 projects into the stator housing 13a with its first end 16a and serves as electrical contact 15 of the plug connection 14 at its second end 16b. 2b also shows that the stator 11 protrudes axially opposite the housing 13 and thereby forms an axial protrusion 20. This water is designed to effect self-centering of the stator 11 by a positive connection with an axial recess in a machine housing in order to accommodate a rotor accommodated in the machine housing.

3 shows a schematic section of an electrical machine 30 with a mounted housing cover 10. The electrical machine 30 has a housing 31, in which a rotor 33 mounted by means of a ball bearing 32 is received. An end region 33a of the rotor 33 with a rotor winding is arranged centered in the stator 11 of the housing cover 10. The axial protrusion 20 of the housing cover is received in an axial recess 34 of the housing 31 of the electrical machine 30 formed around the rotor 33. The housing cover 10 is fastened with fastening means 35, for example screws, and the fastening means of the housing cover 10 to the housing 31 of the machine, so that the end region 33a of the rotor 33 is completely enclosed by the housing cover 10 and the housing 31. At a screw geometry of the housing cover is not in a laminated core of the rotor position sensor stator, but in the cover or housing 13 on another level and another pitch circle, for example radially outside the stator 1 1. The stator 1 1 can be in the assembled state of the housing cover 10, as shown in Fig. 3, for example by means of the plug contact element 14 can be contacted.

The housing cover is a highly integrated solution consisting of the rotor position sensor stator, lead frame and cover with seal and offers an oil-tight, cost-effective solution with few components is connected via internal electrical conductors in the housing cover. When the housing cover is mounted on a rotor, a contact plug can be connected to the electrical plug contact element in order to contact the covered stator. In addition, the axial projection can ensure an arrangement of the stator centered with respect to the rotor.

Reference sign housing cover

stator

Contact point

casing

a first housing section

b second housing section

Integrated electrical plug connection a clamp fastening

electric contact

electrical conductor

a first conductor end area

b second conductor end area

c lead frame

electrical connection of the stator

Clamp connection

Welded joint

axial protrusion

poetry

electrical machine

Machine housing

ball-bearing

rotor

a rotor end area

axial recess

Fasteners

Claims

1. Housing cover (10) for an electrical machine (30), comprising:

a stator (11) integrated in the housing cover (10) of a rotor position sensor for detecting an angular position of a rotor (33) of the electrical machine (30); and an electrical plug connection (14) integrated in the housing cover (10), which is designed to enable electrical contacting of the stator (1 1) on the housing cover (10) by means of a plug contact.

2. housing cover (10) according to claim 1,

wherein electrical contacts (15) of the integrated plug connection (14) are formed by electrical conductors (16) integrated in the housing cover (10), which are electrically connected to respective electrical connections (17) of the stator (1 1).

3. housing cover (10) according to claim 2,

an integrated electrical conductor (16) comprising a lead frame (16c).

4. Housing cover (10) according to one of the preceding claims 2 or 3, wherein an electrical connection of a respective electrical conductor (16) to a respective electrical connection (17) of the stator (1 1) by means of a welded connection (19) or soldered connection is.

5. Housing cover (10) according to one of the preceding claims 2 or 3, wherein an electrical contacting of a respective electrical conductor (16) on a respective electrical connection (17) of the stator (1 1) is carried out by means of a plug connection or clamp connection (18) .

6. housing cover (10) according to claim 1,

wherein electrical contacts (15) of the integrated electrical plug connection (14) are formed by respective electrical connections (17) of the stator (1 1), which are in and / or on a housing (13) of the housing cover (10) from the stator (1 1 ) to the plug connection (14).

7. housing cover (10) according to any one of the preceding claims,

The housing cover (10) has an opening for receiving the rotor (33) on a first side, the housing cover (10) being closed on a second side, which is arranged facing away from the first side, the plug connection ( 14) is formed on the second side of the housing cover (10).

8. housing cover (10) according to any one of the preceding claims,

wherein the stator (1 1) on one side of the housing cover (10) on which an opening for receiving the rotor (33) of the electrical machine (30) in the housing cover (10) is formed axially from a housing part (13) of the The housing cover (10) protrudes so that there is an axial protrusion (20) of the housing cover (10), through which the housing cover (10) is formed, when mounted on an axial recess (34) complementary to the axial protrusion (20). a machine housing (31) of the electrical machine (30) self-centering of the stator (1 1) in order to effect the rotor (33).

9. A method for producing a housing cover (10) for a machine housing (31) of an electrical machine (30), comprising the following steps:

Manufacture of a first housing section (13a) of the housing cover (10) for receiving a stator (1 1) of a rotor position sensor;

Producing a second housing section (13b) of the housing cover (10) by overmolding at least one electrical conductor (16) in an injection molding process; and arranging the first (13a) and the second housing section (13b) so that a first end (16a) of the at least one electrical conductor (16) for contacting the stator from the first housing section (13a) into the second housing section (13b ) protrudes and a second end (16b) of the at least one electrical conductor (16) forms an electrical contact (15) of a plug connector (14) accessible from outside the housing cover (10) for external contacting of the stator (1 1) by means of a plug contact.

10. The method according to claim 9,

wherein the first housing section (13a) and the second housing section (13b) are produced in a common injection molding process.