Spindle drive for a vehicle seat and vehicle seat, particularly for an autonomously driving vehicle

Abstract

The invention relates to a spindle drive (200; 300; 400) for a vehicle seat (100), the spindle drive (200; 300; 400) comprising a threaded spindle (240; 340; 440) arranged in a spindle longitudinal direction (S) and a gear (220; 320; 420), the gear (220; 320; 420) comprising a gear housing (221; 321; 421) and a spindle nut (230; 330; 430) which is in engagement with the threaded spindle (240; 340; 440) and is mounted rotatably relative to the gear housing (221; 321; 421) about the spindle longitudinal direction (S), wherein the spindle nut (230; 330; 430) in the spindle longitudinal direction (S) is supported on a support ring (250; 350; 450), wherein a displacement of the support ring (250; 350; 450) in the spindle longitudinal direction (S) relative to the gear housing (221; 321; 421) is blocked by means of a blocking element (284; 384; 484), wherein the blocking effect of the blocking element (284; 384; 484) can be canceled by means of a pyrotechnic actuator (280; 380; 480).The invention also relates to a vehicle seat (100), in particular for an autonomously driving motor vehicle, the vehicle seat (100) comprising a seat substructure (102) and a backrest (104) hinged to the seat substructure (102), the seat substructure (102) comprising a base (110), a seat frame (120) and an adjustment kinematics (140) acting between the base (110) and the seat frame (120), wherein the adjustment kinematics (140) can be adjusted by means of at least one spindle drive (200; 300; 400) according to the invention.

Description

[0001] The invention relates to a spindle drive for a vehicle seat. The spindle drive comprises a threaded spindle arranged in a spindle longitudinal direction and a gear mechanism. The gear mechanism comprises a gear housing and a spindle nut that engages the threaded spindle and is rotatably mounted relative to the gear housing about the spindle longitudinal direction. The invention also relates to a vehicle seat, in particular for an autonomously driving motor vehicle. State of the art

[0002] DE 10 2010 003 188 A1 discloses a spindle drive for a vehicle seat, the spindle drive comprising a threaded spindle, an electric motor, a gear arranged between the electric motor and the spindle, and a gear housing in which the gear is arranged and through which the spindle is guided.

[0003] DE 10 2018 122 198 A1 discloses an actuator for a motor vehicle, in particular for a motor vehicle seat, comprising an electric motor having an output shaft; a gearbox having a spindle nut and a gearbox housing and connected to the output shaft; a spindle engaging the spindle nut; and a holder at least partially enclosing the gearbox housing.

[0004] In an autonomously driving motor vehicle, a driver does not have to perform any steering and / or braking or acceleration activities, or does not have to do so continuously, while the motor vehicle is in operation; rather, the motor vehicle can be operated independently of the driver's actions. The driver can therefore assume a more comfortable position during autonomous driving than in conventional vehicles. DE 10 2018 203 731 A1 discloses a vehicle seat for an autonomously driving motor vehicle that can assume a tilted position in which a seat part and a backrest are at an angle that allows the vehicle occupant to assume a partially reclining position during autonomous driving. When the vehicle seat is in the upright position, the driver can take over control of the vehicle when autonomous driving is deactivated.

[0005] DE 10 2022 119 627 A1 discloses a vehicle seat for an autonomously driving motor vehicle. The vehicle seat comprises a seat substructure and a backrest hinged to the seat substructure. The seat substructure comprises a base, a seat frame, and adjustment kinematics acting between the base and the seat frame. The adjustment kinematics are designed as a five-bar kinematic system. In a tilted position, the seat frame and the backrest are each tilted backward about an axis parallel to a transverse direction relative to an upright position, thus enabling a partially reclining position of the vehicle driver during autonomous driving. The upright position of the vehicle seat corresponds to a seat setting in which the vehicle driver can safely assume control of the vehicle when autonomous driving is deactivated.

[0006] From WO 2021 / 189089 A1, an actuator is known with a housing, with a pyrotechnic charge and with a piston which merges into a bolt which, in the initial state, protrudes from the housing and is at least partially drawn into the housing when the pyrotechnic charge is ignited. Task

[0007] The object of the invention is to provide a vehicle seat for an autonomously driving motor vehicle that can assume a tilted position in which a seat part and a backrest are at an angle that enables a vehicle occupant, in particular the driver, to assume a partially reclining position during autonomous driving. In the event of an impending or occurring vehicle collision, the vehicle seat should be adjusted more quickly toward an upright position than is possible with vehicle seats known from the prior art. The aim of this is to enable the vehicle occupant to assume control of the vehicle more quickly, or at least to be brought into a more upright position in the event of a vehicle collision that can no longer be avoided or is occurring, in which the risk of injury is minimized.

[0008] The difference between a seat tilt adjustability known from the prior art and the provision of a tilt position is that with a seat tilt adjustment, a change in the angle of inclination of the seat takes place, whereas an angle of inclination of the backrest is not changed, while when assuming a tilt position, both the angle of inclination of the seat and the angle of inclination of the backrest are changed. Solution

[0009] The object is achieved according to the invention by a spindle drive for a vehicle seat, the spindle drive having a threaded spindle arranged in a spindle longitudinal direction and a gear, the gear having a gear housing and a spindle nut which is engaged with the threaded spindle and mounted rotatably about the spindle longitudinal direction relative to the gear housing, wherein the spindle nut is supported on a support ring in the spindle longitudinal direction, wherein a displacement of the support ring in the spindle longitudinal direction relative to the gear housing is blocked by means of a locking element, wherein the locking effect of the locking element can be canceled by means of a pyrotechnic actuator.

[0010] Because the spindle nut is supported on a support ring in the longitudinal direction of the spindle, wherein displacement of the support ring in the longitudinal direction of the spindle relative to the transmission housing is blocked by a locking element, wherein the locking effect of the locking element can be canceled by a pyrotechnic actuator, the support ring and with it the spindle nut and the threaded spindle screwed into the spindle nut can be displaced at high speed in the longitudinal direction of the spindle relative to the transmission housing after the pyrotechnic actuator is triggered. As a result, in the event of an impending or ongoing vehicle collision, the support of the spindle nut on the transmission housing can be canceled, so that the vehicle seat can be adjusted very quickly without the spindle drive, in particular an electric motor of the spindle drive, having to be activated.The displacement of the support ring can occur under a deformation of a thread and / or a support ring guide.

[0011] The spindle longitudinal direction is the position of the threaded spindle in space. The spindle longitudinal direction has two orientations. The spindle nut is supported by the support ring in at least one orientation in the spindle longitudinal direction.

[0012] The spindle drive can be driven by an electric motor. The spindle drive can have an electric motor. The gearbox can be a worm gear. The gearbox can have a helical worm shaft and a worm wheel. The worm shaft can be an output shaft of an electric motor. The worm wheel and the spindle nut can be connected to each other in a rotationally fixed manner in the circumferential direction. The worm wheel and the spindle nut can be axially displaceable relative to each other. The spindle nut can be inserted into the worm wheel. The spindle nut can have a spline profile that interacts with a corresponding spline profile of the worm wheel. The spline profile of the spindle nut can be inserted into the spline profile of the worm wheel. The spline profile of the spindle nut can be arranged on an outer circumference of the spindle nut.The spline profile of the worm gear can be arranged in a central opening of the worm gear. After the pyrotechnic actuator is triggered, the spindle nut and the worm gear can be disengaged by sliding the spindle nut in the longitudinal direction of the spindle relative to the worm gear. In this process, the spline profiles of the worm gear and spindle nut disengage. The spindle nut can protrude from an opening in the gear housing, allowing the spindle to be moved relative to the gear housing.

[0013] The threaded spindle can pass through the gear housing. The support ring can be secured against displacement in the spindle's longitudinal direction relative to a support ring guide by means of the locking element. The support ring can be arranged within a support ring guide. The support ring guide can guide the support ring in the spindle's longitudinal direction after the pyrotechnic actuator has been triggered. The support ring guide can guide the support ring in the spindle's longitudinal direction after the locking effect of the locking element has been removed. The support ring guide can be connected to the gear housing. The support ring guide can be directly connected to the gear housing. The support ring guide can be indirectly connected to the gear housing, for example by means of an adapter part. The support ring guide can be integrated into the gear housing.

[0014] The spindle nut can be rotatable relative to the support ring around the spindle's longitudinal direction. The spindle nut can be supported directly on the support ring. The spindle nut can be supported on the support ring by means of a plain bearing. The spindle nut can be supported on the support ring by means of a rolling bearing.

[0015] The locking element can be a bolt. The bolt can have a round cross-section. The locking element can be a component of the pyrotechnic actuator. The locking element can be connected to a component of the pyrotechnic actuator. The locking element can be connected to a piston of the pyrotechnic actuator.

[0016] The pyrotechnic actuator can comprise a pyrotechnic charge and a piston that merges into the blocking element. The blocking element protrudes from the housing in an initial state and is at least partially retracted into the housing upon ignition of the pyrotechnic charge. The pyrotechnic actuator can be an actuator as described in WO 2021 / 189089 A1.

[0017] The locking element can engage with a locking opening of the support ring. The locking element can be movable, in particular withdrawn, from the locking opening by means of the pyrotechnic actuator.

[0018] The spindle drive can have a support ring guide. The support ring guide can have an internal thread. The support ring can have an external thread corresponding to the internal thread of the support ring guide. The external thread of the support ring and the internal thread of the support ring guide can engage with each other outside of the self-locking mechanism. The locking element can block a relative rotation between the internal thread of the support ring guide and the external thread of the support ring and a resulting displacement of the support ring relative to the support ring guide in the spindle longitudinal direction, in at least one orientation.

[0019] The internal thread of the support ring guide and / or the external thread of the support ring can have a braking geometry that generates a braking torque between the external thread and the internal thread when the external thread is rotated relative to the internal thread. This allows the speed of the relative displacement between the support ring and the support ring guide to be limited or designed accordingly after the pyrotechnic actuator is triggered. The braking geometry can be a geometric deviation from an ideal toothing. The braking geometry can be an elastically preloaded area of ​​the internal thread of the support ring guide and / or the external thread of the support ring.

[0020] An outer diameter of the support ring and an inner diameter of a support ring guide can be matched to each other in such a way that the support ring can only be passed through the support ring guide under a plastic deformation of the support ring guide in the longitudinal direction of the spindle. The outer diameter of the support ring can be larger than a smallest inner diameter of the support ring guide.

[0021] The locking element can engage in an opening of the support ring guide, whereby the locking element can be pulled out of the opening of the support ring guide by triggering the pyrotechnic actuator. An end of the support ring guide facing the support ring can have an inner diameter that is smaller than an outer diameter of the support ring, so that after triggering the pyrotechnic actuator, the support ring can only be guided through the support ring guide after deformation of the support ring guide.

[0022] The object is further achieved by a vehicle seat, the vehicle seat comprising a seat substructure and a backrest hinged to the seat substructure, the seat substructure comprising a base, a seat frame, and adjustment kinematics acting between the base and the seat frame, wherein the adjustment kinematics can be adjusted by means of at least one spindle drive according to the invention. In the event of an impending or occurring vehicle collision, the vehicle seat can be adjusted more quickly toward an upright position than is possible with vehicle seats known from the prior art.

[0023] The adjustment kinematics can have a first front swing arm, a second front swing arm, and a rear swing arm. The first front swing arm can be pivotally connected to the base about a first axis of rotation. A first end region of the first front swing arm can be pivotally connected to the base about the first axis of rotation. The second front swing arm can be pivotally connected to the first front swing arm about a second axis of rotation. A first end region of the second front swing arm can be pivotally connected to a second end region of the first front swing arm about the second axis of rotation. The second front swing arm can be pivotally connected to the seat frame about a third axis of rotation. The rear swing arm can be pivotally connected to the seat frame about a fourth axis of rotation.A first end portion of the rear swing arm can be pivotably connected to the seat frame about the fourth axis of rotation. The rear swing arm can be pivotably connected to the base about a fifth axis of rotation. A second end portion of the rear swing arm can be pivotably connected to the base about the fifth axis of rotation. An angle between the first front swing arm and the second front swing arm can be adjustable by means of the at least one spindle drive. The spindle drive is preferably a component of the adjustment kinematics.

[0024] The at least one spindle drive, in particular a pivoting part of the at least one spindle drive, can be pivotally connected to the base at a first pivot point about a sixth axis of rotation. The at least one spindle drive, in particular a fastening eye of the at least one spindle drive, can be pivotally connected to the second front rocker at a second pivot point about a seventh axis of rotation. A distance between the first pivot point and the second pivot point of the spindle drive can be adjustable by actuating the spindle drive.

[0025] The vehicle seat according to the invention can be a vehicle seat for an autonomously driving motor vehicle. The vehicle seat according to the invention can be used in both an autonomously driving motor vehicle and a conventional vehicle.

[0026] The first, second, third, fourth, fifth, sixth, and seventh axes of rotation preferably run parallel to one another. The first axis of rotation can be arranged below the second axis of rotation. The first axis of rotation can be arranged below the third axis of rotation. The first axis of rotation can be arranged in front of the fourth axis of rotation. The first axis of rotation can be arranged in front of the fifth axis of rotation. The second axis of rotation can be arranged below the third axis of rotation. The second axis of rotation can be arranged in front of the fourth axis of rotation. The second axis of rotation can be arranged in front of the fifth axis of rotation. The third axis of rotation can be arranged in front of the fifth axis of rotation. The fifth axis of rotation can be arranged below the fourth axis of rotation. The sixth axis of rotation can be arranged in front of the first axis of rotation. The first axis of rotation can be arranged below the sixth axis of rotation.The third axis of rotation can be arranged in front of the seventh axis of rotation. The seventh axis of rotation can be arranged below the third axis of rotation. The seventh axis of rotation can be arranged between the second axis of rotation and the third axis of rotation. The seventh axis of rotation can be arranged centrally between the second axis of rotation and the third axis of rotation. The seventh axis of rotation can intersect a connecting line between the second axis of rotation and the third axis of rotation.

[0027] At least one, several or all of the previously described arrangements of the rotation axes relative to one another can be present in the tilted position and / or in an upright position of the vehicle seat.

[0028] In particular, to provide a height adjustment function, an angle of inclination between the first front swing arm and the base, as well as an angle of inclination between the rear swing arm and the base, can be changed by means of an actuator. The actuator can comprise an electric motor and a gear. The actuator can comprise an electric motor, a gear, a spindle nut, and a threaded spindle. The actuator can connect the rear swing arm and the base to one another in an angle-adjustable manner. The actuator can connect the rear swing arm and the base to one another in an angle-adjustable manner and directly, i.e., without the interposition of additional gear elements.

[0029] The base of the vehicle seat can have an adapter. The adapter can be formed or attached to a seat rail of a base designed as a longitudinal adjuster. The longitudinal adjuster can have at least one seat rail and a floor rail connectable to a vehicle floor, on which the seat rail is displaceably guided. The longitudinal adjuster can have a further actuator for displacing the seat rail relative to the floor rail.

[0030] In particular, to provide a seat tilt adjuster, a seat cushion support can be pivotally connected to the seat frame. The angle of inclination between the seat cushion support and the seat frame can be adjusted by means of a further actuator.

[0031] In summary, and in other words, the invention provides a spindle drive for a vehicle seat in which a relaxation function (recline position) can be quickly exited in the event of a crash. For this purpose, a pyroactuator is integrated into the spindle drive, which rotationally locks a threaded wheel (support ring). Once released, the threaded wheel can be pushed away by rotating in the direction of the spindle. A targeted overlap in the thread ensures energy dissipation. By slipping the spindle with a worm gear part, the seat is moved into a design-like position. Figures and embodiments of the invention

[0032] The invention is explained in more detail below with reference to advantageous embodiments illustrated in the figures. However, the invention is not limited to these embodiments. They show: Fig. 1: a highly schematic side view of a vehicle seat according to the invention, Fig. 2: a perspective view of a seat base of a vehicle seat according to the invention in a non-upholstered state, wherein the vehicle seat is in an upper height adjustment position and an upright position, Fig. 3: a side view of the seat base from Fig. 2, wherein the vehicle seat is in a lower height adjustment position and an upright position, Fig. 4: a perspective, partially transparent and sectional view of a spindle drive according to the invention according to a first embodiment, Fig. 5: a perspective, partially sectioned view of essential components of the spindle drive from Fig. 4 before a pyrotechnic actuator is triggered, Fig. 6: an enlarged view of detail VI in Fig. 5, Fig. 7: a perspective, partially sectioned view of essential components of the spindle drive from Fig. 4 after triggering the pyrotechnic actuator, Fig. 8: a perspective, partially sectioned view of essential components of a spindle drive according to the invention according to a second embodiment before triggering a pyrotechnic actuator, and Fig. 9: a highly schematic representation of essential components of a spindle drive according to the invention according to a third embodiment before triggering a pyrotechnic actuator.

[0033] Fig. 1 shows a vehicle seat 100 according to the invention in a highly schematic and simplified manner. The vehicle seat 100 is described below using three spatial directions running perpendicular to one another. A longitudinal direction x, in a vehicle seat 100 installed in the vehicle, runs largely horizontally and preferably parallel to a vehicle longitudinal direction that corresponds to the usual direction of travel of the vehicle. A transverse direction y, which runs perpendicular to the longitudinal direction x, is also oriented horizontally in the vehicle and runs parallel to a vehicle transverse direction. A vertical direction z runs perpendicular to the longitudinal direction x and perpendicular to the transverse direction y. In a vehicle seat 100 installed in the vehicle, the vertical direction z runs parallel to the vehicle's vertical axis.

[0034] The position and direction specifications used, such as left, right, front, rear, top, bottom, and transverse, refer to a viewing direction of an occupant sitting on a seat surface of a seat base 102 (seat part) of the vehicle seat 100 in a usual sitting position, wherein the vehicle seat 100 is installed in the vehicle in a position of use suitable for passenger transport and with an upright backrest 104, and is oriented in the direction of travel as usual. However, the vehicle seat 100 can also be installed in a different orientation, for example, transversely to the direction of travel. Unless otherwise described, the vehicle seat 100 is constructed mirror-symmetrically to a plane running perpendicular to the transverse direction y.

[0035] The vehicle seat 100 can be designed as a so-called integral belt seat, in which a belt system is largely completely integrated into the vehicle seat 100. An upper belt exit point can be integrated into an upper region of the backrest 104. However, the invention is not limited to integral belt seats.

[0036] The backrest 104 is connected to the seat base 102 on both sides by means of a fitting 106 in such a way that the inclination can be adjusted.

[0037] The seat base 102 has a base 110, a seat frame 120 and an adjustment kinematics 140 acting between the base 110 and the seat frame 120.

[0038] In this case, the base 110 comprises a rail on each side for longitudinal adjustment of the vehicle seat 100. Each of the two rails has a seat rail 112 and a floor rail 114 that can be connected to a vehicle floor and on which the seat rail 112 is slidably guided. An adapter 116 is attached to each of the two seat rails 112. The adapter 116 serves in particular to connect elements of the adjustment kinematics 140 to the base 110. The two adapters 116 are connected to each other by a cross bridge 118.

[0039] The two seat rails 112, the two adapters 116 and the cross bridge 118 are components of the base 110.

[0040] The seat frame 120 comprises (viewed in the transverse direction y) a seat frame side part 122 on each side. The seat frame 120 also has a front cross tube 124 and a rear cross tube 126. The two seat frame side parts 122 are arranged at a distance from one another. The front cross tube 124 extends between the two seat frame side parts 122 and is firmly connected on each side to one of the two seat frame side parts 122. The rear cross tube 126 extends between the two seat frame side parts 122 and is rotatably mounted on each side to one of the two seat frame side parts 122. In the present case, the seat frame side parts 122 are one-piece seat frame side parts 122 on each side. Alternatively, however, the two seat frame side parts can also each be composed of several sheet metal parts.

[0041] In this case, the adjustment kinematics 140 (viewed in the transverse direction y) has a five-bar kinematic system on each of the two sides of the seat (right seat side, left seat side). Since the two five-bar kinematic systems are mirror-symmetrical to each other, i.e., each of the five parallel axes of rotation I, II, III, IV, and V runs through a rotary joint of the five-bar kinematic system on both sides, only one of the two five-bar kinematic systems is described below. Unless otherwise stated below, all components of the adjustment kinematics 140 are present on both the right and left sides of the seat.

[0042] The adjustment kinematics 140 has a first front swing arm 142, a second front swing arm 144, and a rear swing arm 146 on each side. The first front swing arm 142 is pivotally connected to the base 110, in this case the adapter 116 of the base 110, about a first axis of rotation I. The second front swing arm 144 is pivotally connected to the first front swing arm 142 about a second axis of rotation II. The second front swing arm 144 is pivotally connected to the seat frame 120 about a third axis of rotation III. The rear swing arm 146 is pivotally connected to the seat frame 120 about a fourth axis of rotation IV. The rear swing arm 146 is pivotally connected to the base 110, in this case the adapter 116 of the base 110, about a fifth axis of rotation V. The rotation axes I, II, III, IV, V run parallel to each other and parallel to the transverse direction y. Each of the rotation axes I, II, III, IV, V runs at a distance from all of the other rotation axes I, II, III, IV, V.

[0043] To provide a height adjustment function, the adjustment kinematics 140 has an actuator 160. By means of the actuator 160, a distance between the base 110 and the seat frame 120 can be adjusted.

[0044] In this case, the two rear rockers 146 are connected, in particular welded, to the rear cross tube 126 in a rotationally fixed manner. The rear cross tube 126 and thus the two rear rockers 146 are pivotally mounted on the seat frame side parts 122 of the seat frame 120 about the fourth axis of rotation IV. Alternatively, the rear cross tube 126 can be connected, in particular welded, to the seat frame side parts 122 of the seat frame 120 in a rotationally fixed manner, and the two rear rockers 146 can be pivotally mounted on the rear cross tube 126.

[0045] The actuator 160 preferably comprises an electric motor 162, a gear 164, a spindle nut, and a threaded spindle 166. The spindle nut is a rotatable and drivable component of the gear 164 and is preferably arranged in a gear housing of the gear 164. The actuator 160 connects the rear rocker arm 146 and the base 110 in an angularly adjustable manner and preferably directly, i.e., not via additional gear elements of the adjustment kinematics 140. For this purpose, the electric motor 162 and the gear 164 are articulated eccentrically to the fifth rotational axis V on the rear rocker arm 146. The threaded spindle 166 is pivotally connected to the adapter 116 of the base 110. The gear 164 is pivotally connected to the rear rocker arm 146 by means of a mounting bracket 168.

[0046] The gear 164 of the actuator 160 has the spindle nut, which can be driven by the motor and into which the threaded spindle 166 is screwed. Actuating the motor rotates the spindle nut, so that the threaded spindle 166 is moved relative to the gear housing and pivots the rear swing arm 146, causing the seat frame side part 122 to change height while simultaneously pivoting the first front swing arm 142 and the second front swing arm 144 in a defined manner. The pivoting movements of the first front swing arm 142 and the second front swing arm 144 that occur during this process will be discussed in more detail below.

[0047] To provide a tilt position of the seat frame 120 and the backrest 104, the adjustment kinematics 140 has a spindle drive 200; 300; 400 on each side of the vehicle seat 100, which is effective between the base 110 and the second front rocker 144 and has an additional pyrotechnic release. Fig. 2 and Fig. 3 show very schematically and generally the vehicle seat 100 according to the invention with a spindle drive 200; 300; 400 according to the invention. The three exemplary embodiments of spindle drives 200; 300; 400 according to the invention described below are shown in the Fig. 2 and Fig. 3 and previously described vehicle seat 100 can be used alternatively. Fig. 4 to 7, a first embodiment of a spindle drive 200 is shown. A second embodiment of a spindle drive 300 is shown in Fig. 8. A third embodiment of a spindle drive 400 is shown in Fig. 9 shown.

[0048] By means of the spindle drives 200; 300; 400, the seat frame 120 can be raised in its front region and pivoted about the fourth rotation axis IV, thus providing the tilted position of the vehicle seat 100. In the tilted position, the seat frame 120 and the backrest 104 are each tilted rearward relative to an upright position about an axis parallel to the transverse direction y, in this case about the fourth rotation axis IV, thus enabling a partially reclining position of the vehicle driver, particularly during autonomous driving. The upright position of the vehicle seat 100 corresponds to a seat setting in which the vehicle driver can safely assume control of the vehicle when autonomous driving is deactivated.

[0049] The two spindle drives 200; 300; 400 are arranged and constructed largely mirror-symmetrically to a plane running perpendicular to the transverse direction y.

[0050] During normal operation, the two spindle drives 200; 300; 400 serve to drive the five-bar kinematics arranged on the respective seat side for transferring the vehicle seat 100 from the upright position to the tilted position and back. Pyrotechnical unlocking of the spindle drives 200; 300; 400 can be performed in a manner described in more detail below in the event of an impending or occurring vehicle collision (crash), in order to enable very rapid adjustment of the vehicle seat 100 from the tilted position to the upright position without having to energize an electric motor 210; 310; 410 of the spindle drive 200; 300; 400. Due to the mirror-symmetrical design, only one of the two spindle drives 200; 300; 400 is described below.

[0051] The spindle drive 200; 300; 400 is both a drive and a component of the adjustment kinematics 140, in that the spindle drive 200; 300; 400 serves as a length-variable coupling between the base 110 and the second front rocker 144.

[0052] The Fig. 4 to 7 show the first embodiment of a spindle drive 200 with pyrotechnic unlocking in the event of a crash.

[0053] The spindle drive 200 has an electric motor 210, a gear 220 with a spindle nut 230, a threaded spindle 240, a support ring 250, a support ring guide 260, a linkage part 270 designed as a fastening bracket and a pyrotechnic actuator 280.

[0054] A first articulation point A1 of the spindle drive 200 is pivotally connected to the base 110 about a sixth axis of rotation VI. For this purpose, a gear housing 221 of the gear 220 and preferably also the electric motor 210 are attached to an articulation part 270, which is pivotally connected to the adapter 116 of the base 110 about the sixth axis of rotation VI. In this case, the articulation part 270 comprises a U-shaped sheet metal element that at least partially encloses the gear housing 221 of the gear 220 and has a web and two legs. The web of the articulation part 270 has a spindle opening 272 for the passage of the threaded spindle 240. Both legs of the articulation part 270 each have, in an end region facing away from the web, a receiving opening 274 for receiving a bolt. The bolts are inserted into bearing eyes 119 of the adapter 116. Thus, the gear 220 is pivotally connected to the base 110 about the sixth rotation axis VI.

[0055] A second pivot point A2 of the spindle drive 200 is pivotally connected to the second front rocker arm 144 about a seventh rotational axis VII. For this purpose, an end of the threaded spindle 240 facing away from the first pivot point A1 has a mounting eye 242, which is pivotally connected, in particular by means of a bolt, to a mounting plate 145 of the second front rocker arm 144. The mounting eye 242 thus forms the second pivot point A2.

[0056] A distance between the first articulation point A1 and the second articulation point A2 of the spindle drive 200 can be adjusted by actuating the electric motor 210, in that the threaded spindle 240 and thus the second articulation point A2 can be displaced relative to the gear housing 221 and the first articulation point A1 by rotating the spindle nut 230.

[0057] The sixth axis of rotation VI runs at a distance from the first axis of rotation I. The sixth axis of rotation VI runs parallel to the first axis of rotation I. The sixth axis of rotation VI is preferably arranged above the first axis of rotation I. The sixth axis of rotation VI is preferably arranged in front of the first axis of rotation I.

[0058] The seventh axis of rotation VII runs at a distance from the third axis of rotation III. The seventh axis of rotation VII runs parallel to the third axis of rotation III. The seventh axis of rotation VII is preferably arranged below the third axis of rotation III. The seventh axis of rotation VII is preferably arranged behind the first axis of rotation I.

[0059] A linear threaded section of the threaded spindle 240 extends in the spindle longitudinal direction S. The terms axial and radial used below refer, unless otherwise stated, to the spindle longitudinal direction S.

[0060] The threaded spindle 240 preferably runs parallel to the first front rocker arm 142, at least in one of several adjustment positions of the spindle drive 200. As a result, the influence of the height adjustment on the inclination angle of the seat base 102 is comparable to a four-bar height adjustment kinematics known from the prior art. Disadvantages that theoretically arise from the five-bar kinematics with regard to the inclination angle of the seat base 102 (unwanted superimposed inclination adjustment due to the height adjustment) are thus avoided.

[0061] The spindle drive 200 acts as a length-adjustable coupling of the adjustment kinematics 140. The first front rocker arm 142, the second front rocker arm 144, the spindle drive 200, and the base 110, together with the first rotational axis I, the second rotational axis II, the sixth rotational axis VI, and the seventh rotational axis VII, form a four-bar kinematics as a partial kinematics of the adjustment kinematics 140, wherein this partial kinematics can be adjusted by adjusting the spindle drive 200. Because the third rotational axis III is arranged at a distance from the seventh rotational axis VII, the tilt position can be achieved by adjusting the four-bar kinematics. Through this four-bar kinematics, a front region of the seat frame 120 is pivotally connected to the base 110 and follows a pivoting movement of the rear rocker arm 146 for height adjustment.

[0062] By means of the electric motor 210, a relative rotation can be generated between the spindle nut 230 of the gear 220 and the threaded spindle 240 threadably engaged with the spindle nut 230, whereby the threaded spindle 240 can be displaced relative to the gear housing 221 of the gear 220. For this purpose, the gear 220 in this case has a worm gear 222, which can be driven by a worm shaft, in particular an output shaft of the electric motor 210.

[0063] The worm gear 222 is mounted in the gear housing 221 of the gear 220 for rotation about the spindle longitudinal direction S. The spindle nut 230 has an internal thread. The spindle nut 230 is screwed onto the threaded spindle 240 for rotation about the spindle longitudinal direction S. The spindle nut 230 has a spline profile 232 radially on the outside, which interacts with a corresponding spline profile 224 of the worm gear 222 such that a rotational movement of the worm gear 222 about the spindle longitudinal direction S results in a rotational movement of the spindle nut 230 about the spindle longitudinal direction S. The corresponding spline profiles 224, 232 of the worm gear 222 and the spindle nut 230 enable an axial relative displacement between the worm gear 222 and the spindle nut 230 along the spindle longitudinal direction S.

[0064] The worm gear 222 is rotatably mounted in the gear housing 221 and is drivable by means of a worm shaft (not shown in the figures), which is connected, for example, to an output shaft of the electric motor 210. The spindle nut 230 is supported in the axial direction on the support ring 250. The spindle nut 230 is mounted axially movably in the worm gear 222; however, before the pyrotechnic actuator 280 is triggered, the support of the spindle nut 230 on the support ring 250 prevents a relative displacement between the worm gear 222 and the spindle nut 230. The gear housing 221 preferably has a through-opening through which the spindle nut 230 is axially movable in the support ring guide 260 after the pyrotechnic actuator 280 is triggered.However, during normal operation of the spindle drive 200, the spindle nut 230 is supported on the support ring 250, so that the spindle nut 230 is axially immovable relative to the gear housing 221.

[0065] The support ring 250 has an external thread 252 and a through-hole 256 through which the threaded spindle 240 is passed. The external thread 252 of the support ring 250 is screwed into an internal thread 264 of the support ring guide 260. The support ring guide 260 has a threaded sleeve 262 into which the internal thread 264 is machined. A support geometry 268, which is firmly connected to the threaded sleeve 262, is axially supported on a support plate 276 of the articulation part 270 in such a way that the support ring guide 260 is axially secured to the articulation part 270. Preferably, the support ring guide 260 is firmly connected to the gear housing 221.

[0066] The pyrotechnic actuator 280 has a housing 282, which is preferably fixedly connected to the articulation part 270 and / or the gear housing 221. The pyrotechnic actuator 280 has a locking element 284, in this case a bolt. The locking element 284 is inserted into a locking opening 254 of the support ring 250. Preferably, the locking element 284 also extends through a passage opening in the threaded sleeve 262 of the support ring guide 260. Because the locking element 284 is inserted into the locking opening 254 of the support ring 250, the external thread 252 of the support ring 250 cannot rotate in the internal thread 264 of the support ring guide 260.

[0067] By triggering the pyrotechnic actuator 280, the locking element 284 can be withdrawn from the locking opening 254. The external thread 252 of the support ring 250 and the internal thread 264 of the support ring guide 260 are engaged with each other outside of the self-locking mechanism, so that a relative rotation occurs between the internal thread 264 and the external thread 252 as soon as the locking element 284 is withdrawn from the locking opening 254 and an axial force acts on the locking element 284.

[0068] In the event of an impending or occurring vehicle collision (crash), the pyrotechnic actuator 280 is triggered if the vehicle seat 100 is in the tilted position or between the tilted position and the upright position. Due to forces acting on the vehicle seat 100, in particular crash forces, inertial forces, and / or weight forces, the spindle nut 230 presses on the support ring 250, which rotates and moves in the support ring guide 260 with axial displacement resulting from the rotation. As a result, the vehicle seat 100 is very quickly moved into the upright position without energizing the electric motor 210.

[0069] In order to limit the speed of the transfer of the vehicle seat 100 in the direction of the upright position in the event of an impending or occurring vehicle collision, the internal thread 264 and / or the external thread 252 have a Fig. 6, which generates a braking torque between the external thread 252 and the internal thread 264 when the external thread 252 is rotated relative to the internal thread 264. In the area of ​​the braking geometry 266, elastic deformation and friction occur between the internal thread 264 and the external thread 252. The relative rotation between the internal thread 264 and the external thread 252 results in a braking torque that limits the speed of the relative movement between the support ring 250 and the support ring guide 260 during the transfer of the vehicle seat 100 toward the upright position and dissipates energy.

[0070] A further actuator 190 is used for longitudinal adjustment, i.e. for moving the seat rail 112 relative to the floor rail 114. The further actuator 190 has, in a manner known per se, an electric motor, a gear, a spindle nut and a spindle arranged in a cavity between the seat rail 112 and the floor rail 114.

[0071] The Fig. The second embodiment of a spindle drive 300 according to the invention shown in Figure 8 corresponds in structure and function to the previously described spindle drive 200, unless otherwise described below. Components with similar or equivalent functions are given reference numerals 100 higher.

[0072] The spindle drive 300 differs from the previously described spindle drive 200 essentially in that, after triggering a pyrotechnic actuator 380 during a transition of the vehicle seat 100 to the upright position, no additional braking torque is provided between an internal thread 364 of a support ring guide 360 ​​and an external thread 352 of a support ring 350. The spindle drive 300 can therefore have a shorter threaded sleeve 362. In this case, the threaded sleeve 362 extends in the axial direction only over the height of the support ring 350.

[0073] Regarding the structure and function of an electric motor 310, a gear 320 (with a worm gear 322 having a splined shaft profile 324 and a spindle nut 330 having a splined shaft profile 332), a threaded spindle 340, and a linkage part with a support plate 376, reference is made to the description of the first exemplary embodiment (spindle drive 200). In particular, the pyrotechnic actuator 380 of the spindle drive 300 also has a housing 382 and a locking element 384 designed as a bolt. During normal use of the vehicle seat 100, the locking element 384 engages in a locking opening 354 of the support ring 350 and thereby prevents a relative rotation between the internal thread 364 of the support ring guide 360 ​​and the external thread 352 of the support ring 350, whereby the spindle nut 330 is held axially relative to a gear housing 321 via its support on the support ring 350.

[0074] In the event of an impending or occurring vehicle collision (crash), the pyrotechnic actuator 380 is triggered if the vehicle seat 100 is in the tilted position or between the tilted and upright positions. Due to forces acting on the vehicle seat 100, the spindle nut 330 presses on the support ring 350, which rotates and moves out of the support ring guide 360 ​​with the resulting axial displacement. As a result, the vehicle seat 100 is very quickly moved into the upright position without energizing the electric motor 310.

[0075] The Fig. The third embodiment of a spindle drive 400 according to the invention shown in Figure 9 corresponds in structure and function to the previously described spindle drive 200, unless otherwise described below. Components with similar or equivalent functions are given reference numerals 200 higher.

[0076] The spindle drive 400 differs from the previously described spindle drive 200 essentially in that a support ring 450 does not have an external thread and a support ring guide 460 does not have an internal thread. As a result, as described in more detail below, after triggering a pyrotechnic actuator 480 during a transition of the vehicle seat 100 to the upright position, the support ring 450 can be moved axially by the support ring guide 460 without any relative rotation occurring between the support ring 450 and the support ring guide 460.

[0077] An outer diameter D1 of the support ring 450 and an inner diameter D2 of the support ring guide 460 are coordinated with one another in such a way that the support ring 450 can be passed through the support ring guide 460 only with a plastic deformation of the support ring guide 460 in the spindle longitudinal direction S. The inner diameter D2 of the support ring guide 460 changes in the axial extent of the support ring guide 460, in particular continuously. The outer diameter D1 of the support ring 450 is presently larger than a smallest inner diameter D2 of the support ring guide 460, so that the support ring guide 460 is elastically or elastically and plastically deformed when the support ring 450 is passed through. An additional braking torque between the support ring guide 460 and the support ring 450 is provided by friction between an outer circumferential surface of the support ring 450 and an inner cylinder surface of the support ring guide 460.The cylindrical inner wall of the support ring guide 460 forms a braking geometry 466 in the areas where the inner diameter D2 is smaller than the outer diameter D1 of the support ring 450.

[0078] With regard to the structure and function of an electric motor 410, a gearbox 420, a worm gear 422 having a splined shaft profile, a spindle nut 430 having a splined shaft profile, a threaded spindle 440 with a fastening eye 442, and a linkage part 470, reference is made to the description of the first exemplary embodiment (spindle drive 200). In particular, the pyrotechnic actuator 480 of the spindle drive 400 also has a housing 482 and a locking element 484 designed as a bolt. During normal use of the vehicle seat 100, the locking element 484 engages through a passage opening in the support ring guide 460 and bears against an end face of the support ring 450, whereby the spindle nut 430 is held axially relative to a gearbox housing 421 via its support on the support ring 450.

[0079] In the event of an impending or occurring vehicle collision (crash), the pyrotechnic actuator 480 is triggered if the vehicle seat 100 is in the tilted position or between the tilted and upright positions. Due to forces acting on the vehicle seat 100, the spindle nut 430 presses on the support ring 450, which moves through the support ring guide 460, deforming the support ring guide 460. As a result, the vehicle seat 100 is very quickly moved into the upright position without energizing the electric motor 410.

[0080] The features disclosed in the above description, the claims and the figures may be important both individually and in combination for the realization of the invention in its various embodiments, as long as they remain within the scope of the claims. List of reference symbols 100 vehicle seats 102 Seat base 104 Backrest 106 Fittings 110 Base 112 seat rail 114 floor rail 116 adapters 118 Cross Bridge 119 Bearing eye 120 seat frames 122 Seat frame side part 124 front cross tube 126 rear cross tube 140 Adjustment kinematics 142 first front swing arm 144 second front swing arm 145 mounting plate 146 rear swing arm 160 actuator 162 electric motor 164 gearboxes 166 threaded spindle 168 mounting brackets 190 Actuator 200 spindle drive 210 electric motor 220 gearbox 221 Gearbox housing 222 Worm gear 224 spline profile 230 spindle nut 232 splined shaft profile 240 threaded spindle 242 Mounting eye 250 support ring 252 external thread 254 locking opening 256 passage opening 260 support ring guide 262 threaded sleeve 264 internal thread 266 Brake geometry 268 Support geometry 270 linkage part 272 spindle opening 274 Recording opening 276 support plate 280 (pyrotechnic) actuator 282 housings 284 locking element, bolt 300 spindle drive 310 electric motor 320 gearbox 321 gearbox housing 322 Worm gear 324 spline profile 330 spindle nut 332 splined shaft profile 340 threaded spindle 350 support ring 352 external thread 354 locking opening 360 support ring guide 362 threaded sleeve 364 internal thread 376 support plate 380 (pyrotechnic) actuator 382 housings 384 locking element, bolt 400 spindle drive 410 electric motor 420 gearbox 421 gearbox housing 422 Worm gear 430 spindle nut 440 threaded spindle 442 Mounting eye 450 support ring 460 support ring guide 466 Brake geometry 470 linkage part 480 (pyrotechnic) actuator 482 housings 484 locking element, bolt I first axis of rotation II second axis of rotation III third axis of rotation IV fourth axis of rotation V fifth axis of rotation VI sixth axis of rotation VII seventh axis of rotation A1 first pivot point A2 second pivot point D1 first diameter D2 second diameter S spindle longitudinal direction x longitudinal direction y transverse direction z Vertical direction QUOTES CONTAINED IN THE DESCRIPTION

[0000] This list of documents submitted by the applicant was generated automatically and is included solely for the convenience of the reader. This 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

[0000] DE 10 2010 003 188 A1

[0002] DE 10 2018 122 198 A1

[0003] DE 10 2018 203 731 A1

[0004] DE 10 2022 119 627 A1

[0005] WO 2021 / 189089 A1 [0006, 0016]

Claims

[1] Spindle drive (200; 300; 400) for a vehicle seat (100), the spindle drive (200; 300; 400) comprising a threaded spindle (240; 340; 440) arranged in a spindle longitudinal direction (S) and a gear (220; 320; 420), the gear (220; 320; 420) comprising a gear housing (221; 321; 421) and a spindle nut (230; 330; 430) which is in engagement with the threaded spindle (240; 340; 440) and is rotatably mounted relative to the gear housing (221; 321; 421) about the spindle longitudinal direction (S), characterized by in that the spindle nut (230; 330; 430) is supported in the spindle longitudinal direction (S) on a support ring (250; 350; 450), wherein a displacement of the support ring (250; 350; 450) in the spindle longitudinal direction (S) relative to the gear housing (221; 321; 421) is blocked by means of a blocking element (284; 384; 484), wherein the blocking effect of the blocking element (284; 384; 484) can be canceled by means of a pyrotechnic actuator (280; 380; 480). [2] Spindle drive (200; 300; 400) according to claim 1, characterized by that the locking element (284; 384; 484) is a bolt. [3] Spindle drive (200; 300; 400) according to claim 1 or 2, characterized by that the blocking element (284; 384; 484) is a component of the pyrotechnic actuator (280; 380; 480), in particular is connected to a piston of the pyrotechnic actuator (280; 380; 480). [4] Spindle drive (200; 300) according to one of claims 1 to 3, characterized by that the locking element (284; 384) is in engagement with a locking opening (254; 354) of the support ring (250; 350), wherein the locking element (284; 384) can be moved, in particular pulled out, from the locking opening (254; 354) by means of the pyrotechnic actuator (280; 380). [5] Spindle drive (200; 300) according to one of claims 1 to 4, characterized bya support ring guide (260; 360), wherein the support ring guide (260; 360) has an internal thread (264; 364) and the support ring (250; 350) has a corresponding external thread (252; 352), wherein the external thread (252; 352) and the internal thread (264; 364) are in engagement with one another outside of the self-locking, wherein the locking element (284; 384; 484) blocks a relative rotation between the internal thread (264; 364) and the external thread (252; 352) and thus a displacement of the support ring (250; 350) relative to the support ring guide (260; 360) in the spindle longitudinal direction (S). [6] Spindle drive (200) according to claim 5, characterized by that the internal thread (264) and / or the external thread (252) have a braking geometry (266) which, when the external thread (252) is rotated relative to the internal thread (264), generates a braking torque between the external thread (252) and the internal thread (264). [7] Spindle drive (400) according to one of claims 1 to 3, characterized bythat an outer diameter (D1) of the support ring (450) and an inner diameter (D2) of a support ring guide (460) are matched to one another in such a way that the support ring (450) can be guided through the support ring guide (460) in the spindle longitudinal direction (S) exclusively under a plastic deformation of the support ring guide (460), in particular the outer diameter D1 of the support ring (450) is larger than a smallest inner diameter (D2) of the support ring guide (460). [8] Vehicle seat (100), in particular for an autonomously driving motor vehicle, the vehicle seat (100) comprising a seat substructure (102) and a backrest (104) hinged to the seat substructure (102), the seat substructure (102) comprising a base (110), a seat frame (120) and an adjustment kinematics (140) acting between the base (110) and the seat frame (120), wherein the adjustment kinematics (140) is adjustable by means of at least one spindle drive (200; 300; 400) according to one of claims 1 to 7. [9] Vehicle seat (100) according to claim 8, characterized by that the adjustment kinematics (140) has a first front rocker (142), a second front rocker (144) and a rear rocker (146), wherein the first front rocker (142) is pivotally connected to the base (110) about a first axis of rotation (I), the second front rocker (144) is pivotally connected to the first front rocker (142) about a second axis of rotation (II), the second front rocker (144) is pivotally connected to the seat frame (120) about a third axis of rotation (III), the rear rocker (146) is pivotally connected to the seat frame (120) about a fourth axis of rotation (IV), and the rear rocker (146) is pivotally connected to the base (110) about a fifth axis of rotation (V), wherein an angle between the first front rocker (142) and the second front rocker (144) is adjustable by means of the at least one spindle drive (200; 300; 400). [10] Vehicle seat (100) according to claim 8 or 9, characterized by in that the at least one spindle drive (200; 300; 400), in particular a linkage part (270; 470) of the at least one spindle drive (200; 300; 400), is pivotably connected to the base (110) at a first linkage point (A1) about a sixth axis of rotation (VI), and in that the at least one spindle drive (200; 300; 400), in particular a fastening eye (242; 442) of the threaded spindle (240; 340; 440), is pivotably connected to the second front rocker (144) at a second linkage point (A2) about a seventh axis of rotation (VII).

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