ACTUATOR FOR A MOTOR VEHICLE, IN PARTICULAR FOR A MOTOR VEHICLE SEAT

Abstract

Actuator (10, 210) for a motor vehicle, in particular a motor vehicle seat, with a) an electric motor (20) having an output shaft (24), b) a gearbox (100, 200) connected to the output shaft (24) and comprising a gearbox housing (120, 220) and c) a gearbox holding device (160, 260) which pivotably supports the gearbox housing (120, 220) about a pivot axis (165, 265), wherein at least one shaft section (126, 226) of the gearbox housing (120, 220) aligned with the pivot axis (165, 265) is at least partially encompassed by a retaining bracket (170, 270) of the gearbox holding device (160, 260), d) a worm gear (130) of the gearbox (100) which is rotationally fixed to the output shaft (24), wherein the worm gear (130) is engaged with a spindle nut (140), wherein the spindle nut (140) is rotatably mounted in the gearbox housing (120, 220), and the spindle nut (140) interacts with a spindle (150) such that a rotation of the spindle nut (140) leads to a relative displacement between the spindle (150) and the gearbox housing (120, 220), wherein the output shaft (24) is arranged outside the retaining bracket (170, 270), characterized in that the shaft section (126) borders at least partially on a through-opening (124) of the gearbox housing (120) or partially projects into it, and the retaining bracket (170) passes through the through-opening (124).

Description

[0001] The invention relates to an actuator for a motor vehicle, in particular for a motor vehicle seat, comprising an electric motor having an output shaft, a gearbox connected to the output shaft and having a gearbox housing, and a gearbox holding device pivotably supporting the gearbox housing about a pivot axis, wherein a shaft section of the gearbox housing aligned with the pivot axis is at least partially encompassed by a retaining bracket of the gearbox holding device. State of the art

[0002] DE 10 2006 005 499 A1 discloses an actuator in which a gear mount completely encloses a gear housing, so that an output shaft of an electric motor is also enclosed by the gear mount. The gear housing is rotatably mounted in the gear mount in such a way that fitting inaccuracies and tolerances are compensated for by relative rotation between the gear housing and the gear mount.

[0003] DE 10 2008 017 017 A1 discloses an actuator whose gear housing is mounted in a bracket. A pivot bearing is provided between the gear housing and the bracket, and a support is provided between the gear housing and the bracket, which is opposite the pivot bearing. The bracket largely encloses the gear housing, and an output shaft of an electric motor runs inside the bracket.

[0004] CH 647 305 A5 discloses a motor-driven linear thrust device with a push rod that is driven by a screw spindle with a nut. Both the nut and the screw spindle are individually rotatably mounted and each have their own drive. The linear thrust device has a housing that includes two pins for pivotally mounting the linear thrust device.

[0005] From EP 2 610 104 A2 an actuator with a worm gear is known in which a gear holder completely encloses a gear housing, so that an output shaft of an electric motor is also enclosed by the gear holder.

[0006] DE 10 2008 050 255 A1 discloses a linear drive with a linear stroke for adjusting movably mounted parts, in particular a piece of seating furniture, wherein the linear drive has a housing with a profile section and a drive device with the interacting drive components motor, rotary element, gear for transmitting and converting the motor torque to the rotary element and thrust element, the thrust element is mounted in a torsionally fixed and displaceable manner on a base and the rotary element acts on the thrust element on the output side for the linear displacement of the thrust element relative to the rotary element over the stroke.

[0007] Another actuator of this type is known from the document DE 10 2008 043 904 A1. Task

[0008] The invention is based on the object of improving an actuator of the type mentioned at the outset, in particular of providing a space-optimized and cost-effective gear holding device. Solution

[0009] This object is achieved according to the invention by an actuator having the features of patent claim 1.

[0010] Because the output shaft is located outside the retaining bracket, the retaining bracket does not completely encompass the gearbox housing, eliminating the need for additional space on the side of the output shaft facing away from the retaining bracket. This provides a space-optimized and cost-effective gearbox mounting device.

[0011] Advantageous embodiments, which can be used individually or in combination with one another, are the subject of the subclaims.

[0012] The gear holder can be used in all known actuators where a pivoting movement between the gear holder and the gear is advantageous. Electric motors with an integrated or attached reduction gear connected to another gear unit can also be used. In this case, the term "output shaft of the electric motor" refers to the output shaft of the integrated or attached reduction gear unit.

[0013] The actuator according to the invention comprises a spindle nut that can be driven at least indirectly by the output shaft, which is rotatably mounted in the transmission housing, and in which the spindle nut interacts with a spindle such that rotation of the spindle nut leads to a relative displacement between the spindle and the transmission housing. The moving spindle can, for example, actuate a seat adjuster or a window lifter in a motor vehicle.

[0014] A minimized spindle length and a more pleasant end stop noise for a given adjustment range of the actuator can be achieved by providing a spindle stop that projects radially from the spindle in at least one end region of the spindle, which in an end position of the adjustment range of the actuator rests against an end face of the spindle nut and thereby defines the end position.

[0015] A spindle stop with a plastic or rubber section that rests against the end face of the spindle nut further improves the impact noise behavior of the actuator.

[0016] According to the invention, the shaft section is at least partially adjacent to a through-opening in the transmission housing or protrudes into a through-opening in the transmission housing, and the retaining bracket extends through this through-opening. The retaining bracket can thus encompass and support the shaft section or at least form part of a bearing point. This advantageously provides a particularly space-optimized transmission holding device.

[0017] Preferably, the shaft section, and with it the pivot axis of the gear mounting device, are arranged radially offset from the output shaft. This allows the output shaft to be arranged outside the mounting bracket to save space. Preferably, the pivot axis and the output shaft run parallel but offset from each other.

[0018] Preferably, the retaining bracket comprises precisely two U-shaped brackets, each with a first bearing shell, which, together with a second bearing shell of a locking part, form two circumferential hubs for supporting two shaft sections. The locking part closes the retaining bracket in such a way that each shaft section is completely enclosed by the gear holding device in its circumferential direction.

[0019] The gearbox mounting device can have one, two, or more bearing points for the gearbox. The mounting bracket comprises a first bearing shell for each of the bearing points. Several first bearing points can also merge into one another. The locking part comprises a second bearing shell for each of the bearing points. A first bearing shell and the second bearing shell complement each other to form a hub that supports the respective shaft section, with the angular ranges of the two bearing shells complementing each other to form a circumferential cylinder. For example, the first bearing shell and the second bearing shell are each designed as half-cylinders, each encompassing the pivot axis by 180°.

[0020] A particularly simple installation of the gear retaining device to the shaft sections of the gear housing can be achieved by connecting the locking part to the retaining bracket using a clip connection. Spring arms with lugs are preferably formed on the locking part. During assembly of the gear retaining device, the lugs spring into recesses in the retaining bracket, thus ensuring a positive connection opposite to the joining direction, which advantageously lies largely parallel to the spindle.

[0021] Alternatively or in addition to the clip connection, the locking element can be positively connected to the retaining bracket in a direction parallel to the pivot axis. For this purpose, at least one plug-in profile of the retaining bracket can engage in a complementarily shaped locking element opening.

[0022] To connect the actuator to another component, such as a seat structure, the gear retaining device has at least one opening for the passage of a fastening means, in particular a screw or rivet. Preferably, a central axis of the fastening means, aligned in the longitudinal direction of the fastening means, runs parallel to the spindle. As a result, the fastening means is subjected to comparatively low loads. In contrast to the actuator devices known from the prior art, the gear retaining device and the fastening means are subjected to less compressive load.

[0023] The shaft sections can also be designed as pins protruding laterally from the gearbox housing.

[0024] The shaft sections can be formed in one piece with the gearbox housing, for example injection-molded, or attached to the gearbox housing.

[0025] The actuator according to the invention offers an optimization of stability compared to the prior art, thereby optimizing noise behavior, efficiency and wear resistance. Figures and embodiments of the invention

[0026] The invention is explained in more detail below with reference to two advantageous embodiments illustrated in the figures. However, the invention is not limited to these embodiments. They show: Fig. 1: a perspective view of a first embodiment of an actuator according to the invention in a first end position of the spindle, Fig. 2: a Fig. 1 corresponding view with a partially sectioned gearbox housing, Fig. 3: a perspective view of the actuator from Fig. 1 in a second end position of the spindle, Fig. 4: a Fig. 3 corresponding view with a partially sectioned gearbox housing, Fig. 5: a perspective view of the actuator from Fig. 1 without gear holding device, Fig. 6: a detailed view from Fig. 1 to the area of ​​the gearbox holding device, Fig. 7: an exploded view of the gear holding device from Fig. 1, Fig. 8: a sectional view of the actuator from Fig. 1 in the area of ​​the gearbox holding device, Fig. 9: a Fig. 8 similar sectional view, Fig. 10: a perspective view of a second embodiment of an actuator according to the invention, Fig. 11: a Fig. 10 corresponding view with a partially sectioned gearbox housing of the second embodiment and Fig. 12: a Fig. 10 corresponding view with an exploded view of the gear holding device of the second embodiment.

[0027] In the Fig. Figures 1 to 9 show a first embodiment of an actuator 10 for a motor vehicle, in particular for a motor vehicle seat. The actuator 10 comprises an electric motor 20, a gear 100 connected to the electric motor 20, and a gear retaining device 160.

[0028] The electric motor 20 includes an output shaft 24, which is non-rotatably connected to a worm 130 of the gearbox 100. The worm 130 engages with a spindle nut 140. The spindle nut 140 is part of the gearbox 100 and, in a conventional manner, engages with a spindle 150.

[0029] The gear unit 100 comprises a gear housing 120, which accommodates the worm 130 and the spindle nut 140. The gear housing 120 has an approximately cylindrical portion for receiving the worm 130 and another approximately cylindrical portion for receiving the spindle nut 140, which portion is oriented toward the spindle and perpendicular to the cylindrical receiving portion for the worm 130.

[0030] The transmission mounting device 160 pivotally supports the transmission housing 120 about a pivot axis 165. The transmission mounting device 160 can, for example, be attached to a vehicle seat structure of the motor vehicle seat.

[0031] The spindle 150 extends through the gear housing 120. For this purpose, the gear housing 120 has a first housing opening 121 and a second housing opening 122 through which the spindle 150 extends. A bearing bushing 128 for supporting a first of two ends of the spindle nut 140 is inserted into the second housing opening 122. A second end of the spindle nut 140 is mounted directly in the gear housing 120. The spindle 150 also extends through the bearing bushing 128.

[0032] In an area adjacent to the second housing opening 122, the approximately cylindrical portion of the gear housing 120, which accommodates the spindle nut 140, is widened in two diametrically opposite areas and each provided with a through-opening 124. The two through-openings 124 are elongated holes, with the longitudinal axes of the elongated holes extending in the direction of the largest clear width of the through-openings 124 running parallel to a central axis of the spindle 150.

[0033] In a region of the through-opening 124 facing away from the worm 130, the gear housing 120 and the inner walls of the through-openings 124 are shaped such that each through-opening 124 is delimited by a shaft section 126 with a circular cross-section. The two shaft sections 126 define the pivot axis 165, about which the gear housing 120 can pivot relative to the gear holding device 160. This allows for compensation of fitting inaccuracies and tolerances within the actuator 10 and / or positional tolerances of the actuator 10 relative to a component to be driven. In addition, some components to be driven, such as four-bar height adjusters, may fundamentally require limited rotation of the actuator 10.

[0034] The gear holding device 160 comprises a holding bracket 170 and a locking part 180, which are connected to one another, in this case clipped, and between them support the two shaft sections 126 of the gear housing 120.

[0035] During the assembly process, the spindle nut 140 and then the bearing bush 128 are inserted into the gear housing 120 through the second housing opening 122. The gear retaining device 160 can then be attached to the gear housing 120.

[0036] The retaining bracket 170 comprises two U-brackets 174 arranged offset from one another in the direction of the pivot axis 165, which are connected to one another by a web 176. Each of the two U-brackets 174 consists of a semicircularly curved profile section, to each of whose ends a linear plug-in profile 175 is connected. A first bearing shell 171 is formed in the inner circumference of the semicircularly curved profile section, which extends semi-cylindrically around the pivot axis 165 over an angle of approximately 180°.

[0037] Each of the two U-bolts 174 has two retaining bracket openings 172 running parallel to the spindle 150. The outer sides of the two U-bolts 174 each have a notch-shaped recess 179, which is part of a clip connection described in more detail below.

[0038] The locking part 180 has an approximately flat, rectangular basic geometry, through the center of which a first locking part opening 181 extends. The first locking part opening 181 is designed in the shape of an elongated hole, wherein the longitudinal axis of the elongated hole extending in the direction of the largest clear width of the locking part opening 181 runs perpendicular to the pivot axis 165 and serves as a through hole for the spindle 150.

[0039] A second locking part opening 182 is arranged in each of the four corner regions of the locking part 180. In the direction of the material thickness of the locking part 180, at least one, in this case every, second locking part opening 182 is divided into two sections by a stepped shoulder 183. A first section faces the pivot axis 165 and has a cross-section complementary to the plug-in profile 175 of the U-shaped bracket 174. A second section of the second locking part opening 182, facing away from the pivot axis 165, has a diameter that is smaller than the largest extension of the cross-section of the plug-in profile 175.

[0040] Two semi-cylindrical second bearing shells 185 extend in the direction of the pivot axis 165 and, together with one of the first bearing shells 171 of the retaining bracket 170, each form a rotating hub which rotatably supports one of the two shaft sections 126.

[0041] A spring arm 188 is arranged in each of the four corner areas of the locking part 180, extending perpendicular to the flat basic geometry of the locking part 180 and in the direction of the retaining bracket 170. A lug 189 is machined onto the free-standing end of each spring arm 188. The lugs 189 engage in the recesses 179 of the retaining bracket 170, thus creating the previously mentioned, known clip connection consisting of the spring arm 188, lug 189, and recess 179.

[0042] The plug-in profiles 175 of the retaining bracket 170 are inserted into the second locking part openings 182 of the locking part 180, so that the locking part 180 is positively connected to the retaining bracket 170 in a direction parallel to the pivot axis 165.

[0043] The second locking part openings 182 are each aligned with one of the retaining bracket openings 172. Fastening means not shown in the figures, in particular screws, run through the retaining bracket openings 172 and the second locking part openings 182, serve to fasten the gear holding device 160 and, in the assembled state, additionally secure the connection between the retaining bracket 170 and the locking part 180 of the gear holding device 160. The central axes of the fastening means each run parallel to one another and largely parallel to the spindle 150.

[0044] The output shaft 24 is arranged completely outside the transmission holding device 160.

[0045] The actuator 10 is continuously adjustable between a first end position of the spindle 150 and a second end position of the spindle 150. The end positions are defined by stops.

[0046] The first end position is reached when a first spindle stop 151, which is firmly connected to the spindle 150, runs from the outside against an area of ​​the gear housing 120 surrounding the first housing opening 121. In the opposite direction, the second end position is reached when a second spindle stop 152, which is firmly connected to the spindle 150, has passed through the first locking part opening 181 and the bearing bush 128 and runs against an end face of the spindle nut 140 facing the second spindle stop 152.

[0047] The first spindle stop 151 is a circular disc whose outer diameter is larger than the inner diameter of the first housing opening 121.

[0048] The second spindle stop 152 is a circular disc whose outer diameter is smaller than the inner diameter of the second housing opening 122, smaller than the inner diameter of the first locking part opening 181, and slightly smaller than the inner diameter of the bearing bushing 128. This allows the second spindle stop 152 to pass through the first locking part opening 181 and the bearing bushing 128 and avoid contact with any of these components. This reduces the required length of the spindle 150.

[0049] The second spindle stop 152 consists of two disc-shaped sections made of different materials. A region facing the spindle nut 140 is made of a plastic or rubber material. A region facing away from the spindle nut 140 is made of a metal material, in particular steel.

[0050] In the Fig.10 to 12 show a second embodiment of an actuator 210. The actuator 210 comprises a gear 200, which differs from the gear 100 of the first embodiment by a gear housing 220 modified in certain details. Furthermore, a gear holding device 260 differs from the gear holding device 160 of the first embodiment. Components of the actuator 210 that are modified compared to the first embodiment have reference numerals 100 higher. Unless otherwise described below, the second embodiment corresponds to the first embodiment.

[0051] The actuator 210 comprises an electric motor 20 and the gear 200 connected to the electric motor 20, the gear housing 220 of which is pivotally mounted about a pivot axis 265 by a gear holding device 260.

[0052] Two shaft sections 226 are formed on the gear housing 220, which protrude laterally from the gear housing 220 on both sides and perpendicular to a spindle 150 extending through the gear housing 220. The two shaft sections 226 define a pivot axis 265 about which the gear housing 220 can pivot relative to the gear holding device 260. The two shaft sections each have a circular cross-section with a flattened portion at one point.

[0053] The gear holding device 260 comprises a holding bracket 270 and a locking part 280, which are connected to one another, for example clipped, and between them support the two shaft sections 226 of the gear housing 220.

[0054] The retaining bracket 270 is designed in the form of a U-bracket, the legs of which extend approximately perpendicular to the spindle 150. In an inner region between the legs of the retaining bracket 270, a first bearing shell 271 is formed, which extends semi-cylindrically around the pivot axis 265 over an angle of approximately 180°.

[0055] The locking part 280 also has a U-shaped basic form with two legs, wherein the legs of the locking part 280 extend approximately parallel to the spindle 150. Both legs of the locking part 280 each have a second semi-cylindrical bearing shell 285 on the side.

[0056] The length of the legs of the locking part 280 corresponds to the distance between the legs of the retaining bracket 270. The legs of the retaining bracket 270 accommodate the locking part 280 between them. The two semi-cylindrical second bearing shells 285, together with the first bearing shell 271 of the retaining bracket 270, each form a rotating hub, which rotatably supports one of the two shaft sections 226.

[0057] The retaining bracket 270 has several through holes in the area of ​​the leg ends (not shown in the figures). These through holes serve to attach the retaining bracket 270 to a structural part, for example, a seat structure. The center axes of the fastening means each run approximately perpendicular to the spindle 150.

[0058] The output shaft 24 is arranged completely outside the transmission holding device 260.

[0059] The features disclosed in the above description, the claims and the drawings may be important both individually and in combination for the realization of the invention in its various embodiments. List of reference symbols 10, 210 Actuator 20 electric motor 24 Output shaft 100, 200 gearbox 120, 220 gearbox housing 121 first housing opening 122 second housing opening 124 passage opening 126, 226 wave section 128 bearing bush 130 snail 140 spindle nut 150 spindle 151 first spindle stop 152 second spindle stop 160, 260 Gearbox holding device 165, 265 swivel axis 170, 270 support bracket 171, 271 first bearing shell 172 Holding bracket opening 174 U-bolts 175 plug-in profile 176 jetty 179 Deepening 180, 280 locking part 181 first locking part opening 182 second locking part opening 183 paragraph 185, 285 second bearing shell 188 spring arm 189 Nose

Claims

[1] Actuator (10, 210) for a motor vehicle, in particular a motor vehicle seat, with a) an electric motor (20) having an output shaft (24), b) a gearbox (100, 200) connected to the output shaft (24) and having a gearbox housing (120, 220) and c) a gear holding device (160, 260) which pivotably supports the gear housing (120, 220) about a pivot axis (165, 265), wherein at least one shaft section (126, 226) of the gear housing (120, 220) aligned with the pivot axis (165, 265) is at least partially encompassed by a retaining bracket (170, 270) of the gear holding device (160, 260), d) a worm (130) of the gear (100) which is connected in a rotationally fixed manner to the output shaft (24), wherein the worm (130) is in engagement with a spindle nut (140), wherein the spindle nut (140) is rotatably mounted in the gear housing (120, 220), and the spindle nut (140) cooperates with a spindle (150) such that rotation of the spindle nut (140) leads to a relative displacement between the spindle (150) and the gear housing (120, 220), wherein the output shaft (24) is arranged outside the retaining bracket (170, 270), characterized by that the shaft section (126) at least partially adjoins a through opening (124) of the gear housing (120) or partially projects into it and the retaining bracket (170) passes through the through opening (124). [2] Actuator (10) according to claim 1, characterized bythat in at least one end region of the spindle (150) a spindle stop (152) is provided which projects radially from the spindle (150) and which, in an end position of an adjustment range of the actuator (10), rests against an end face of the spindle nut (140) and thereby defines the end position. [3] Actuator (10, 210) according to one of the preceding claims, characterized by that the gear holding device (160, 260) comprises a closing part (180, 280) which closes the holding bracket (170) in such a way that the shaft section (126, 226) is completely enclosed by the gear holding device (160, 260) in its circumferential direction. [4] Actuator (10, 210) according to one of the preceding claims, characterized by that the retaining bracket (170, 270) has a first bearing shell (171, 271). [5] Actuator (10, 210) according to claims 3 and 4, characterized bythat the closing part (180, 280) has a second bearing shell (185, 285) and the first bearing shell (171, 271) and the second bearing shell (185, 285) complement each other to form a hub supporting the shaft section (126, 226). [6] Actuator (10) according to one of claims 3 to 5, characterized by that the locking part (180) is connected to the retaining bracket (170) by means of a clip connection (179, 188, 189). [7] Actuator (10) according to one of claims 3 to 6, characterized by that the locking part (180) is positively connected to the retaining bracket (170) in a direction parallel to the pivot axis (165). [8] Actuator (10) according to one of the preceding claims, characterized bythat the gear holding device (160) has at least one opening (172, 182) for passing through a fastening means, in particular a screw, for fastening the gear holding device (160) to a further component and a central axis of the fastening means aligned in the longitudinal direction of the fastening means runs largely parallel to the spindle (150).

Images