DE102012203222A1 - Housing part for driving unit for actuating moving parts of car, has groove for receiving radial joint, which radially ensures sealing of part, where wall of groove comprises projections that carry out interlocking connection with joint - Google Patents

Abstract

The part (10) has a peripheral groove (56) for receiving a radial joint (28), which radially ensures sealing of the part relative to a assembly direction (12) with respect to a base body of a housing (9). An interior wall of the groove comprises projections (60), which carry out an interlocking connection with the radial joint. The radial joint comprises cavities (59) extending along the direction, and the projections penetrate in the cavities, where the radial joint is an injected part and molded in the groove. The projections are provided on two opposite side walls. An independent claim is also included for a method for realizing a housing part on which a radial joint is formed.

Description

State of the art

The invention relates to a housing part for a drive unit, and a method for producing such a housing part according to the preamble of the independent claims.

There are many drive devices are known in which the housing consists of different housing parts, which are sealed watertight for use in a humid environment against each other. For example, shows the DE 200 04 338 U1 a power window drive, in which a plug-in module can be inserted into a corresponding opening of a transmission housing. In this case, the plug-in module is a housing part, which has a cover surface for closing the opening in the gear housing with a molded-on connector. On the inside of the housing part, a radial seal with a plurality of sealing lips is formed, which seals the gear housing when inserted in an approximately rectangular shaft. Such radial seals are usually molded onto the housing part or inserted into a groove. When mounting the housing part, however, there is a risk that the radial seal is pulled out of the groove, whereby the tightness of the housing is affected by such drive units.

The EP 1763917 B1 shows a housing part to which a radial seal is molded. Again, the component of the radial seal can detach from the smooth surface of the component of the housing part during its assembly, and thereby lead to leakage problems of the drive unit.

Advantages of the invention

The housing part according to the invention, as well as the method for producing such a housing part with the features of the independent claims have the advantage that the radial seal also by the action of large shear forces in the groove of the. By the positive engagement of the integrally formed on the groove inner wall extensions in corresponding recesses in the radial seal Housing remains anchored. This ensures that the drive unit is always reliably sealed against the environment during assembly of the housing part equipped with the radial seal.

The features set out in the dependent claims advantageous refinements of the housing part according to the invention, and its manufacturing method are possible. Particularly favorable, the extensions can be formed as moldings on the groove inner wall by injection molding, since in this case the specific design of the formations can be easily and inexpensively realized by the shape of the injection mold. For the injection molding of the housing part with the groove, a hard plastic can be used as the first component, whereby a stable, dimensionally stable housing part is created.

The radial seal with the integrally formed recesses for receiving the formations of the groove inner wall is formed from a second, elastic component, so that the sealing lips of the radial seal elastically deform when inserted into the housing opening under radial pressure, and be pressed against the radial inner wall of the housing opening. As a result, the housing is also reliably sealed against water. The production of the radial seal by means of injection molding is particularly favorable, wherein the radial seal is either inserted into the groove as a separately manufactured injection molded part (rubber material, for example NBR) or injected directly into the groove (thermoplastic elastomer, TPE).

The cover element and the circumferential groove are preferably formed approximately rectangular so that perpendicular to the lid member, for example, a circuit board can be accommodated. As a result, both the groove, as well as the radial seal each have two short sides and two long sides, with which the housing part is sealed against the inner wall of the opening of the housing main body. If the formations are each formed only on the long sides or only on the short sides, these formations can be produced very easily by means of a two-part injection mold - and in particular removed from the injection mold. The short sides can also have the same length as the long sides, so that the groove and the radial seal is formed approximately square.

It is advantageous to form the formations on the two side walls of the groove, which extend approximately perpendicular to the mounting direction, since then occurring during assembly shear forces can be accommodated in and against the mounting direction to hold the radial seal in the groove. If the formations are arranged opposite one another on the two side walls, then these directly opposite form connections improve the anchoring of the radial seal within the groove, even with a strong radial tensile load of the radial seal.

By forming a plurality of formations on a side wall of the groove next to each other, the adhesion of the radial seal is increased within the groove, this effect also by the formation of a textured surface of the groove inner wall can be achieved. In this case, this structuring can be limited to certain sections of the side walls of the groove, or on the entire groove inner wall - including the bottom surface of the groove - are formed. However, the greatest effect is achieved in the arrangement of the formations or structuring, in the central region of the side walls with respect to their radial extent.

Due to the extension of the formations in the mounting direction, an undercut with respect to the radial direction is formed in combination with the corresponding recesses in the radial seal. The positive engagement between the molding in the corresponding recess may in this case have a ramp-shaped, or triangular or semicircular cross-section. The surface of the formations can thus be formed pointed or curved. A sawtooth-shaped surface of the formations facilitates the radial insertion of the radial seals in the groove and reliably prevents a radial extraction of the radial seals from the groove.

If the radial seal is injected directly into the groove of the housing part, other geometries for the formations can be selected, which form a stronger undercut, since the liquid component can fill in any desired shape during injection.

The housing part preferably has a plug on the outside, which serves for the electrical supply of the electric drive unit. In this case, both the motor current and sensor signals can be passed through the cover element of the housing part in order to produce the electrical contact with corresponding electrical connections in the interior of the drive unit. If a receptacle for a printed circuit board is formed on the inside of the housing part, the electrical contacts for controlling the drive unit can be guided via the printed circuit board. In this case, on the inside or on the circuit board electrical / electronic components can be arranged, which are used for operating the drive unit.

Particularly advantageous for a defined interface of the drive unit different plug-in modules in the form of a kit can be provided. The plug-in modules can be designed for simple drive units as a pure connection plug modules, or be designed for the rotational position detection of the drive unit as a sensor module with a sensor system. If a plurality of electronic functions are to be provided for the drive unit, an arbitrarily large printed circuit board with the corresponding electronic components, such as, for example, relays or a PWM control can be made available by means of an electronic module. By means of the defined opening in the housing base body, a modular system can be made available with the different plug-in modules, with which very different electronic functions can be adapted to the requirements of the gear unit.

The housing part with the radial seal can be produced in a particularly favorable manner by means of a two-component plastic injection molding method, in which first the housing part is sprayed, for example, with hard plastic. In this case, the volume for the second elastic component, for example an elastomer, is recessed by an insert. After removal of the insert is then injected in a second step, the material of the radial seal in the same injection mold. By means of such easy-to-handle two-component injection molding methods, on the one hand the moldings on the groove inner wall can be formed on the one hand by means of the first component, and on the other hand the recess on the radial seal can be molded on by injection molding of the second component. This creates a nearly ideal fit between the formations and the recesses.

It is particularly favorable to arrange the parting plane of the molding tool of the injection molding apparatus through the middle of the side length of the short sides or the long sides of the rectangular groove. By pulling these C-shaped tool halves, the housing part with the formations can be easily removed from the tool without the housing part must be deformed during removal in order to solve the formation of the undercut can.

In one embodiment, the housing part additionally axial clearance compensation elements, which are preferably integrally molded with the radial seal. In this case, the housing part with the radial seal by means of locking elements which engage in corresponding counter-elements of the housing, are reliably connected to this. By dispensing with separate connecting means between the housing part and the housing, the assembly process can be automated.

drawings

Embodiments of the invention are illustrated in the drawings and explained in more detail in the following description.

Show it 1 a perspective view of a housing part,

2 a representation of another embodiment of a housing part and a section through a drive unit, and

3 a section through a further embodiment of a housing part during assembly in the housing body.

Description of the embodiment

In 1 is a housing part 10 shown, which is suitable, a housing body 9 a drive unit 11 complete watertight. The housing base, not shown 9 the drive unit consists for example of a transmission housing 8th and / or an electronics housing 7 and has, for example, an approximately rectangular opening 13 with a radial inner wall 15 on, in the for closing the housing body 9 the housing part 10 in mounting direction 12 is introduced. The housing part 10 has a cover element 14 with an inside 16 and an outside 18 on. On the outside 18 is for example a plug 20 molded, with electrical contacts 22 through the lid element 14 on the inside 16 be performed. Furthermore, on the housing part 10 various electronic components 42 be arranged, which is part of an electronic module 36 or a plug-in module 37 or a sensor module 38 are passing through the housing part 10 be formed. On the inside 16 the lid element 14 is a circumferential wall 24 with a radial outer surface 26 molded, at the a circumferential radial seal 28 is arranged. The radial seal 28 is also approximately rectangular with rounded at the corners radii 30 formed around the corresponding rectangular opening 13 seal in the housing. In this case, the radial seal 28 two opposite short sides 34 and two opposite long sides 35 on. The radial seal 28 For example, has one, or two or more sealing lips 31 on which a radial sealing surface 40 form. When inserted into the housing body 9 becomes the radial seal 28 due to occurring radial forces 32 perpendicular to the mounting direction 12 against the radial inner wall 15 of the housing body 9 pressed and thereby elastically deformed. The radial seal 28 is in a groove 56 arranged on the radial outer surface 26 the surrounding wall 24 is trained. Here is the radial seal 28 in the groove 56 optionally injected, or manufactured as a separate sealing element and then into the groove 56 inserted. The housing part 10 is preferably made of a hard plastic and the radial seal 28 made of an elastic material, for example a thermoplastic elastomer or of a rubber material. On an inner wall 57 the groove 56 are in 1 not visible) formations 60 formed, the form-fitting in corresponding recesses 59 in the radial seal 28 intervention. To the radial seal 28 are axial extensions 46 molded, as axial play compensation elements 48 serve. The clearance compensation elements 48 On the one hand, they are supported on the inside 16 the lid element 14 from and form on the opposite side of an axial stop surface 50 for the housing body 9 , Due to the shape and dimensions of the clearance compensation elements 48 a spring force can be set for a latching connection 52 between the housing part 10 and the housing body 9 necessary is. For this purpose are on the housing part 10 For example, locking lugs 52 trained in appropriate in 2 illustrated locking elements 53 of the housing body 9 intervention. As an alternative to the locking elements 52 . 53 can the housing part 10 be attached by means of separate connection means, including on the housing part 10 Recordings 54 for the separate connection means, such as screws or rivets, are formed.

In 2 is another embodiment of a housing part 10 shown in which the plug 20 with the contacts made 22 approximately at right angles to the cover element 14 extends. The housing part 10 is in this embodiment as a sensor or electronic module 38 . 36 with a recording 44 for a printed circuit board 45 formed when inserting with the electrical contacts 22 is connected. Likewise, fork-shaped contact elements 22 for the power supply of the electric motor 6 when inserted in mounting direction 12 directly connected with corresponding (not shown) motor contacts. On the circuit board 45 is for example a sensor device 43 arranged, preferably Hall sensors 47 , which after the finished assembly of the plug-in module with a sensor magnet 41 the drive unit 11 interact. The drive unit 11 has an electric motor 6 on, its armature shaft 4 , one in the gearbox 8th arranged transmission 5 drives. For example, on the armature shaft 4 a worm gear 66 arranged with a worm wheel 67 meshes that torque via a coupling element 68 to an output element 69 forwards. The gearbox 8th forms together with the electronics housing 7 and the electric motor 6 the housing base 9 at which the opening 13 for receiving the housing part 10 is arranged. On the inner wall 15 are as locking elements 53 Recesses formed in the assembled state, the locking lugs 52 take up. On the surrounding wall 24 of the housing part 10 is the groove 56 shaped, in which the radial seal 28 is inserted before the housing part 10 in the drive unit 11 is inserted. The groove inner wall 57 has two in mounting direction 12 opposite side walls 58 on where the formations 60 are formed. In the embodiment, the formations 60 only on one, the drive unit 11 facing side wall 58 molded and have a pointed, or triangular cross-section 61 on. The formations 60 extend against the mounting direction 12 and are about in the middle of the sidewall 58 arranged with respect to their radial extent. The recesses 60 are here only on the long sides 35 the groove 56 (or the radial seal 28 ) and preferably extend completely over the entire length of the long sides 35 , On the short sides 34 are here no formations 60 arranged so that the formations 60 when removing the two injection mold halves perpendicular to the plane of the paper 2 can be easily removed from the mold halves. Alternatively, the formations 60 even on the short sides 34 be arranged, with the two short sides 34 also the same length as the two long sides 35 can be trained.

In 3 is a further embodiment shown in which the housing part 10 in the opening 13 is inserted. In this case, the edge of the opening 13 an insertion bevel 64 on, through which the sealing lips 31 when inserted in mounting direction 12 be deformed. This occurs in the radial seal 28 a shearing force 65 contrary to the mounting direction 12 on top of the radial seal 28 out of the groove 56 pull out. To prevent this, are on both opposite side walls 58 formations 60 formed in corresponding recesses 59 in the radial seal 28 protrude into it. In 3 is an example on the left side a molding 60 with a ramp-shaped cross section 61 shown, on the right side two adjacent recesses 60 , for example, a semicircular cross-section 61 having a curved surface. Again, the formations 60 approximately halfway up the side walls 58 arranged, wherein in a variant, not shown, three formations 60 can be arranged side by side. The side walls 58 and / or the groove bottom 62 the groove inner wall 57 can also be formed with a profiled surface - for example, with a triangular or sawtooth profile.

The housing part 10 in 3 is preferably produced by means of a two-component injection molding process, wherein in a first step the housing part 10 from a first component - for example, hard plastic - is injected.

During this first spraying operation, an insert is inserted into the mold, which forms the mold for the second component of the radial seal 28 having. After removal of the insert, the second component is injected into the injection mold in a second step, wherein as a second component for the radial seal 28 an elastic material, preferably a thermoplastic elastomer is used. In an alternative injection molding process, the two components are molded in two different nests of a tool, wherein the housing part 10 from one nest to the other nest. The injection molding tool not shown in detail preferably has a parting plane which extends through the central region of the side length of the short sides 34 or the long sides 35 leads. Here is the rectangular shape of the groove 56 divided into two C-shaped halves of the two injection molds. By pulling these C-shaped injection molding tools, the housing part 10 with the formations 60 can be easily removed from the tool, without need for the formation of the formations 60 a slide must be used, or when removing the housing part 10 an undercut would have to be overcome.

It should be noted that many possible combinations of the individual features are possible with regard to the embodiments shown in the figures and the description. For example, the concrete shape and the cross-section of the radial seal 28 adapted to the respective applications. Similarly, the number, the cross section 61 and the arrangement of the formations 60 at the groove inner wall 57 and the recesses 59 at the radial seal 28 be varied. So can the recesses 60 also on the short sides 34 be arranged, or the recesses 60 not over the entire circumferential length of the pages 34 . 35 but only on certain portions of these pages 34 . 35 , Also, the shape or function of the housing part 10 not limited to the embodiments and may, for example, for pure plug modules 37 or for cover elements 14 without electrical contacts 22 be used. The housing part according to the invention preferably takes place 10 Application for actuators in motor vehicles, for example for plug, sensor or electronic modules 37 . 38 . 36 of power window or sunroof drives.

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 20004338 U1 [0002]
• EP 1763917 B1 [0003]

Claims (13)

Housing part ( 10 ) for a drive unit ( 11 ), in particular for adjusting moving parts in the motor vehicle, along a mounting direction ( 12 ) in a housing base ( 9 ), wherein the housing part ( 10 ) a circumferential groove ( 56 ), in which a radial seal ( 28 ) is arranged, which the housing part ( 10 ) radially to the mounting direction ( 12 ) relative to the housing base body ( 9 ), characterized in that within the groove ( 56 ) on a groove inner wall ( 57 ) Formations ( 60 ) are formed, which with the radial seal ( 28 ) a positive connection ( 63 ) form. Housing part ( 10 ) according to claim 1, characterized in that the housing part ( 10 ) is formed as an injection molded part - in particular of a first hard plastic component - and the formations ( 60 ) on the groove inner wall ( 57 ) are molded in one piece. Housing part ( 10 ) according to one of claims 1 or 2, characterized in that the radial seal ( 28 ) is formed from a second, elastic component - preferably a thermoplastic elastomer or a rubber material - and at least one in the radial direction ( 33 ) extending sealing lip ( 31 ) - in particular for watertight sealing of the housing base body ( 9 ). Housing part ( 10 ) according to one of the preceding claims, characterized in that the circumferential groove ( 56 ) substantially rectangular with two short sides ( 34 ) and two long pages ( 35 ) is formed, wherein the formations ( 60 ) only on the two long sides ( 35 ) or only on the two short sides ( 34 ) are formed. Housing part ( 10 ) according to one of the preceding claims, characterized in that the formations ( 60 ) in itself transverse to the mounting direction ( 12 ) extending side walls ( 58 ) of the groove inner wall ( 57 ) are formed, and the formations ( 60 ) in the mounting direction ( 12 ). Housing part ( 10 ) according to one of the preceding claims, characterized in that the formations ( 60 ) on both opposite side walls ( 58 ) - in particular approximately opposite - are formed. Housing part ( 10 ) according to one of the preceding claims, characterized in that the formations ( 60 ) in a middle area ( 55 ) of the side walls ( 58 ) with respect to the radial direction ( 33 ) are arranged, in particular exactly one or two or three formations ( 60 ) are arranged side by side. Housing part ( 10 ) according to one of the preceding claims, characterized in that the formations ( 60 ) a curved or ramped or pointed cross section ( 61 ), and preferably an undercut ( 63 ) with the radial seal ( 28 ) with respect to the radial direction ( 33 ) form. Housing part ( 10 ) according to one of the preceding claims, characterized in that the radial seal ( 28 ) Recesses ( 59 ), which in the mounting direction ( 12 ), and the formations ( 60 ) positively in the recesses ( 59 ), wherein in particular the radial seal ( 28 ) is formed as an injection molded part and preferably to the groove ( 56 ) is injected. Housing part ( 10 ) according to one of the preceding claims, characterized in that on the housing part ( 10 ) an outer plug ( 20 ) for electrically contacting the drive unit and / or a printed circuit board ( 45 ) is arranged, which in particular a sensor arrangement for rotational position detection ( 43 ) of the drive unit ( 11 ). Drive unit ( 11 ) with a housing part ( 10 ) according to one of the preceding claims, characterized in that the housing part ( 10 ) as a plug-in module ( 36 . 37 . 38 ) of the drive unit ( 11 ), wherein the plug-in module as an electronic module ( 36 ) or as a sensor module ( 38 ) or as a plug-in module ( 37 ) is formed, and the plug-in module ( 36 . 37 . 38 ) opposite the drive unit ( 11 ) by means of the radial seal ( 28 ) is sealed. Method for producing a housing part ( 10 ) with an integrally formed radial seal ( 28 ) - in particular according to one of the preceding claims -, wherein in a first step the housing part ( 10 ) with the groove ( 56 ) is injected from a first component, and in a second step, the radial seal ( 28 ) from a second component into the groove ( 56 ) is injected, characterized in that during injection molding of the second component, these a positive connection ( 63 ) with the formations ( 60 ) on the groove inner wall ( 57 ) of the first component. A method according to claim 11, characterized in that for producing the substantially rectangular groove ( 56 ) the injection molding tool has at least two tool parts which are suitable for removing the housing part ( 10 ) across the mounting direction ( 12 ) along the longitudinal extent of the formations ( 60 ) along the side wall ( 58 ) are moved apart so that the formations ( 60 ) without elastic deformation of the housing part ( 10 ) from the tool parts.

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