Windscreen Wiper Motor Prior Art

The invention relates to a windscreen wiper motor according to the preamble of claim 1 . The invention also relates to a suppression housing according to the invention, comprising at least one plug connection element for use in a windscreen wiper motor.

A windscreen wiper motor according to the preamble of claim 1 is already known from DE 39 30 144 A1 . It has a carbon holder plate, which carries carbon elements, which in turn bear against the outer periphery of a commutator. The car- bon elements are electrically connected usually by strands to voltage supply lines, which discharge into a plug region of a housing of the windscreen wiper motor. A cable harness or plug on the vehicle side is used to supply voltage to the windscreen wiper motor via the plug region. For suppression, it is usual for the voltage supply lines to be connected within the windscreen wiper motor to the electrical connections (strands) of the carbon elements via a suppression device. To this end, the components of the suppression device are to be arranged in a suppression housing consisting of plastic. Furthermore, the components comprise at least one plug connection element consisting of sheet metal and formed as a stamped and bent part. In the case of a suppression housing installed in the housing of the windscreen wiper motor, the plug connection element is connected to plug contacts, which are arranged in the plug region, and which can be contacted with the aforementioned plugs of the cable harness. In the case of the known suppression device, the plug connection element is inserted into the suppression housing in an installation direction for this purpose. In addition, the plug connection element is received in a fixed manner in its final position in the suppression housing. The plug connection element is axially positioned or fixed in the suppression housing by a connection to a metal sheet, which is connected to a suppression coil. The fixing process is therefore carried out via an additional component, which is not part of the plug connection element. A relatively complex installation of the components is therefore necessary.

Disclosure of the Invention

Proceeding from the aforementioned prior art, the object of the invention is to develop a windscreen wiper motor according to the preamble of claim 1 in such a way that a particularly simple installation of the plug connection element in the suppression housing is enabled, with which the position of the plug connec- tion element in the suppression housing is already unambiguously defined during the installation process. This object is achieved in accordance with the invention with a windscreen wiper motor having the features in claim 1 in that the at least one plug connection element is guided in an installation direction on introducing into the suppression housing through guide elements and is fixed in the final position by a detent connection in the suppression housing, and in that the guide elements form parts of guide slots on the base of the suppression housing, into which side walls of the plug connection element project. The invention therefore provides a combination of guide means on the one hand for defined guiding and installation of the plug connection element in the suppres- sion housing, and a detent connection on the other hand, which securely fixes the plug connection element in its axial final position in the suppression housing. In other words, this means that the plug connection element is unambiguously positioned and fixed in the suppression housing merely by a corresponding embodiment of the plug connection element and of the suppression housing. Due to the guide elements, incorrect installation or incorrect positioning of the plug connection element in the suppression housing is ruled out on the one hand, and on the other hand the guide elements make it possible to position the plug connection element in a plane perpendicular to the installation direction. Due to the detent connection, the plug connection element is in turn fixed in a direction parallel to the installation direction, such that the plug connection element is fixed in all three spatial axes as a result of a combination of the guide elements with the detent connection. Furthermore, due to the use of a detent connection, additional components for fastening the plug connection element in the suppression housing can be omitted, and the detent connection enables a particularly simple installation, which, in the event of manual installation, provides tactile feedback to the operator as soon as the plug connection element is locked in its final position. In addition, as a result of a design in which the guide elements form regions of guide slots on the base of the suppression housing, into which side walls of the plug connection element project, it is ensured that the plug connection element is guided not only inwardly (based on its cross section), but additionally outwardly. Advantageous developments of the windscreen wiper motor according to the invention are disclosed in the dependent claims.

In an embodiment of the detent connection that is preferred in terms of production, it is proposed that the detent connection is formed by at least one recess, preferably in the form of an aperture on the at least one plug connection element and a snap-in hook cooperating with the recess in the final position of the at least one plug connection element, which hook is preferably formed in one piece on the suppression housing. This embodiment of the detent connection is therefore particularly advantageous, since the plug connection element is nor- mally formed as a stamped and bent part and therefore the provision of the (additional) aperture for the detent connection can be formed easily by a corresponding change to the mold without great capital outlay. Furthermore, the suppression housing is usually formed from plastic by means of injection molding, and therefore the provision of the additional snap-in hook can be implemented very easily and at relatively low cost in this case too by a corresponding embodiment of the mold for forming the suppression housing.

A particularly reliable fixing of the plug connection element, with which, in addition, a tilting of the plug connection element in particular is also reliably pre- vented, can be achieved if on opposite sides of the at least one plug connection element respectively a recess is arranged, which cooperates with respectively a snap-in hook. A design of this type of the detent connection additionally has the advantage that, even if an individual snap-in hook fails, whether during opera- tion or as a result of incorrect installation, the other snap-in hook fixes or holds the plug connection element in the suppression housing.

In addition, the guide elements has extensions projecting from a base of the suppression housing in the direction of the plug connection element, which extensions project in a form-fitting manner into the opening cross section of the plug connection element. With an arrangement of this type, it is made possible to use the plug connection element on the side opposite the extensions to contact the plug (of the vehicle-side cable harness), so that, compared to a sup- pression housing according to the prior art, no additional installation space is required in the base area.

A further advantageous embodiment of the invention concerns the case in which the suppression housing comprises at least one (additional) structural element in the form of a printed circuit board, on which a (additional) suppression circuit is arranged in particular. In this case, the additional component (printed circuit board) on introducing into the suppression housing is guided in a form-fitting manner by additional guides formed in the suppression housing. Due to the additional guides for the component, said component can be held in a defined position within the suppression housing and, with the occurrence of accelerations or external forces, can introduce these directly into the suppression housing and thus keep them away from the other components. A mechanically particularly robust suppression device is thus created. The invention additionally comprises, as the smallest structural unit, a suppression housing, comprising guides and a detent connection for the fixed reception of at least one plug connection element in a windscreen wiper motor.

Further advantages, features and details of the invention will emerge from the following description of preferred exemplary embodiments and with the help of the drawing, in which: figure 1 shows an exploded illustration of the main component parts of a windscreen wiper motor according to the invention, figure 2 shows a side view of a carbon holder plate with suppression housing fastened thereto, as is used with a windscreen wiper motor according to figure 1 , figure 3 to

figure 5 each show sections in the planes III - III to V - V in figure 2, figure 6 shows a section in the plane VI - VI of figure 4, figure 7 shows a perspective view of the component parts of a suppression device and of a suppression housing, figure 8 shows an individual illustration of a plug connection element according to figure 7 in side view, and figure 9 shows a section in the plane IX - IX of figure 8.

Like components and functionally like components are provided with like reference numerals in the figures.

The main component parts of a windscreen wiper motor 10 according to the invention are illustrated in an exploded view in figure 1. The windscreen wiper motor 10 has a housing 1 1 , which has a transmission housing region 12 and a motor housing region 13. The transmission housing region 12 and the motor housing region 13 are interconnected in one piece in the illustrated exemplary embodiment by means of a single-part design of the housing 1 1. Of course, it also lies within the scope of the invention to use housing designs with which the transmission housing region 12 and the motor housing region 13 are formed by separate components, which are then interconnected. The motor housing region 13 can be closed by a motor housing cover 15 on the side opposite the transmission housing region 12 with interpositioning of a ring seal 14.

An armature shaft 18 is rotatably mounted in bearing elements 18 inside the housing 11. On the side facing the transmission housing region 12, the armature shaft 18 has a worm toothing 20. The worm toothing 20 meshes with a toothing 22 formed on the periphery of a gearwheel 21. The gearwheel 21 has a spindle 23, which is connected outside the housing 1 1 to a lever 24 in a rota- tionally engaged manner. The lever 24 is connected in particular to a wiper rod assembly (not illustrated) of a windscreen wiper apparatus and is used to move windscreen wipers (likewise not illustrated) back and forth. The transmission housing region 12 is closed on the side opposite the lever 24 by means of a transmission housing cover 25, in particular by means of screws 26. The transmission housing cover 25 has a plug region 27 with plug contacts (not illu- strated) arranged therein, the windscreen wiper motor 10 being electrically con- tactable via said plug contacts to the plugs (not illustrated) of the cable harness of the motor vehicle for voltage supply.

The armature shaft 18 carries an armature laminated core 28 consisting of a multiplicity of interconnected individual sheets, winding wires 29 being would around the teeth of said core in a manner known per se. The winding wires 29 are electrically connected, in particular soldered or welded, to a commutator 30 arranged in a rotationally engaged manner on the armature shaft 18. The commutator 30 cooperates with a plurality of carbon elements 31 , which are ar- ranged within the carbon holders 32 visible in figure 2, and which are pressed by means of compression springs against the outer periphery of the commutator 30. The carbon holders 32 are arranged together with the carbon elements 31 on a carbon holder plate 35 that is round in cross section or in plan view. The carbon holder plate 35 is in turn received or fixed in a defined position within the housing 1 1 in corresponding receptacles, for example pin-shaped extensions.

In accordance with figure 2, the carbon elements 31 are electrically connected to voltage supply lines 37 via electrical connections, in particular in the form of strands 36. The voltage supply lines 37, which are connectable via the plug contacts in the plug region 27 and the cable harness to the on-board voltage of the motor vehicle, comprise a plurality of components or portions, as can be seen in particular with reference to figure 2. A suppression device 40, which has a plu- rality of suppression chokes 41 in accordance with figure 7, is thus identified as parts of the voltage supply line 37. Wire ends 42 of the suppression chokes 41 are electrically conductively connected to the strands 36 at the carbon holder 32, in particular by welded connections. The suppression device 40 further comprises an optionally provided printed circuit board 43 with components ar- ranged thereon, in particular in the form of SMD components 44, for example in order to achieve particularly good suppression. A shield plate 45 can also be seen, through which the line portions 46 of the voltage supply lines 37 are passed. The line portions 46 are each connected by means of welded connections 47 to a respective plug connection element 50 in order to form two wiper stages.

The plug connection elements 50 visible in particular in figures 7 to 9 consist of sheet metal and is formed as a stamped and bent part. They comprise plug connection vanes 51 , 52 contacted against one another, which can be electri- cally connected to the contact plugs (not illustrated) in the plug region 27 and therefore to the cable harness by introducing the contact plugs between the plug connection vanes 51 , 52. A base region 53 of the plug connection element 50, from the upper side of which the plug connection vanes 51 , 52 proceed, can also be seen and is rectangular in cross section. Apertures 57, 58 that are rec- tangular in cross section and are arranged symmetrically about a longitudinal plane 56, which is located between the slotted plug connection vanes 51 , 52, are formed in the region of side walls 54, 55 of the base region 53. The cross section of the base region 53 is formed in the side opposite the plug connection vanes 51 , 52 as an open cross section with a substantially rectangular end face 59. The plug connection element 50 additionally has horizontally bent contact portions 61 , 62, on which the line portions 46 rest, and at which the welded connections 47 are formed (figure 3). The components described thus far of the suppression device 40 are arranged in a suppression housing 65 (with the exception of a partial region of the suppression chokes 41 and of the wire ends 42). The suppression housing 65 is constructed as a single-part suppression housing 65 from plastic and is preferably produced by means of injection molding. On the side facing the carbon holder plate 35, the suppression housing 65 has four retaining feet 66 formed as pin-shaped extensions, said feet projecting through corresponding through- openings or through-bores in the carbon holder plate 35 and being deformed on the side of the carbon holder plate 35 remote from the suppression housing 65 by means of a press-fit (as can be seen in particular with reference to figure 2), in such a way that the suppression housing 65 is fastened to the carbon holder plate 35 in a fixed manner.

On the side remote from the carbon holder plate 35, the suppression housing 65 has a closed termination wall 67, on which a partition wall 64 is integrally formed, which separates the two plug connection elements 50 from one another. It is key, after installation of the components of the suppression device 40 in the suppression housing 65 and after the installation of the suppression housing 65 on the carbon holder plate 35, that the module consisting of the carbon holder plate 35 and suppression housing 65 reaches the region of the plug connec- tion 27 of the housing transmission cover 25 via the suppression housing 65 when installed into the housing 1 1 of the windscreen wiper motor 10. As can be seen in particular with reference to the side view according to figure 2, the suppression housing 65 has two side walls 68, 69, wherein the suppression housing 65 is formed as an open suppression housing 65, with the exception on the side facing the termination wall 67. This is provided in particular in view of the desired contacting of the termination sheet 45 with the transmission housing region 12. The components of the suppression device 40 are installed into the suppression housing 65 perpendicularly to the drawing plane of figure 2 in the direction of the arrow in figure 7. In accordance with the invention, the plug connection elements 50 are received within the suppression housing 65 in a fixed manner in the final position of said elements. To this end, the suppression housing 65 has guide elements in the form of plate-like extensions 72, 73 projecting from the base region 71 of the suppression housing 65 in the direction of the two plug connection elements 50, as can be seen in particular from a comparison of figures 2 to 6. The extensions 72, 73 have a width that corresponds to the width of the opening cross section of the two plug connection elements 50, as can be seen in particular with reference to figure 4. The extensions 72, 73 are additionally matched to the cross section of the plug connection elements 50 in the region of the base region 53, in such a way that, in the final position of the plug connection elements 50 illustrated in figure 4, they reach approximately as far as 2/3 of the height of the base region 53. It can also be seen in particular with reference to figure 4 that groove-like guide slots 74, 75 are formed parallel to the side walls 54, 55 in the base region 71 of the suppression housing 65 and are used to receive the side walls 54, 55 of the plug connection elements 50 in a form-fitting manner.

In accordance with figure 6, a further guide slot 76 is additionally formed between the termination wall 67 and the extension 72, and receives a front wall 77 of the plug connection elements 50 in a form-fitting manner. By means of the extensions 72, 73 described thus far and also the guide slots 74 to 76, the plug connection elements 50 can be positioned exactly within the suppression housing 65 in a plane perpendicular to the installation direction (arrow 70). In order to additionally prevent the plug connection elements 50 from moving against the installation direction (arrow 70) after installation in the suppression housing 65, the suppression housing 65 additionally has two snap-in hooks 78, 79 for each of the plug connection elements 50, said snap-in hooks cooperating with the apertures 57, 58 on the side walls 54, 55 and each forming a detent connection. Once the components of the suppression device 40 have been installed, in particular the plug connection elements 50, these are fixed in the suppression housing 65 in accordance with figure 5 once the detent connections have been formed and therefore against the installation direction (arrow 70) on the one hand, and on the other hand are additionally also received in the suppression housing 65 in a fixed manner in a plane perpendicular to the installation direc- tion due to the aforementioned guides.

Furthermore, two rib-like guide webs 81 , 82 are formed on the side walls 68, 69 of the suppression housing 65, the printed circuit board 43 being received in a form-fitting manner between said webs on introduction of the components of the suppression device 40, for example the shield plate 45, or by corresponding additional grooves, and are thus additionally received in a fixed manner in the suppression housing 65.

The windscreen wiper motor 10 described thus far or the components of the suppression housing 40 can be altered or modified in a versatile manner, without departing from the scope of the inventive concept. This concerns a fixed reception of the plug connection elements 50 within the suppression housing 65, and therefore the plug connection elements 50 are arranged rigidly within the suppression housing 65 after installation, both in the direction of their instal- lation and in a plane perpendicular to the installation direction.

List of reference signs

10 windscreen wiper motor

1 1 housing

12 transmission housing region

13 motor housing region

14 ring seal

15 motor housing cover

18 armature shaft

19 bearing element

20 worm toothing

21 gearwheel

22 toothing

23 spindle

24 lever

25 transmission housing cover

26 screw

27 plug region

28 armature laminated core

29 winding wire

30 commutator

31 carbon element

32 carbon holder

35 carbon plate

36 strand

37 voltage supply line

40 suppression device

41 suppression choke

42 wire ends

43 printed circuit board

44 SMD component

45 shield plate

46 line portion 47 welded connection

50 plug connection element

51 plug connection vane

52 plug connection vane

53 base region

54 side wall

55 side wall

56 longitudinal plane

57 aperture

58 aperture

59 end face

61 contact portion

62 contact portion

64 partition wall

65 suppression housing

66 retaining foot

67 termination wall

68 side wall

69 side wall

70 arrow

71 base region

72 extension

73 extension

74 guide slot

75 guide slot

76 guide slot

77 front wall

78 snap-in hook

79 snap-in hook

81 guide web

82 guide web