LENGTH ADJUSTER, METHOD FOR MOUNTING A LENGTH ADJUSTER AND VEHICLE SEAT

Description

[0001] The invention relates to a longitudinal adjuster, comprising at least one pair of rails formed from a first rail and a second rail, wherein the first rail and the second rail are displaceable relative to one another, in particular in a longitudinal direction, wherein the first rail and the second rail alternately engage around one another to form an inner channel, wherein a spindle nut connected to the second rail and a spindle operatively connected to the spindle nut are arranged in the inner channel, wherein a spindle gear drivable by means of a motor and interacting with the spindle is arranged on the first rail, wherein the spindle nut is fixed to the second rail by means of a first fixing element and a second fixing element. The invention further relates to a method for assembling such a longitudinal adjuster and to a vehicle seat. State of the art

[0002] DE 10 2017 218 492 A1 discloses a generic longitudinal adjuster for a vehicle seat, the longitudinal adjuster comprising at least one pair of rails formed from a first seat rail and a second seat rail which is displaceable in the longitudinal direction relative to the first seat rail, wherein the seat rails alternately engage around one another to form an inner channel, wherein a spindle nut mounted on the second seat rail and a spindle operatively connected to the spindle nut are arranged in the inner channel, wherein a gear driveable by a motor and cooperating with the spindle is arranged at a front end of the first seat rail, wherein the spindle is mounted in the gear at a front end portion of the spindle and in a pivot bearing of the first seat rail at a rear end portion of the spindle. The spindle nut is fixed to the second rail by means of two fixing elements.

[0003] DE 10 2005 023 095 A1 discloses a drive device for a motor vehicle seat in a sliding device. The drive device for use with a motor vehicle seat sliding device comprises mating fixed and movable rail parts that can be moved between a forward position and a rearward position. The drive device comprises an elongated spindle, a spindle nut, a gear, and a mounting device. The spindle defines a spindle axis and has a longitudinally extending spindle thread. The spindle nut can be securely fastened to a first rail part and has an internal thread that can engage with the spindle thread. The gear can be mounted to a different rail part and selectively rotates the spindle about the spindle axis.The spindle of the drive device is provided with a spindle wheel which, when the drive device is mounted, extends outwards through spindle wheel openings of the movable rail part.

[0004] DE 10 2006 000 193 A1 discloses a seat sliding device comprising a system with a floating threaded spindle and a fixed nut. The nut is attached to the lower rail, while the threaded spindle rotates through it, allowing the upper structure to move forward and backward. When this system is used, the nut is attached to the lower rail.

[0005] From DE 10 2019 122 928 B3, a longitudinal adjuster is known, comprising at least one pair of rails formed from a second rail and a first rail displaceable in the longitudinal direction relative to the second rail, wherein the rails alternately engage around one another to form an inner channel, wherein a spindle nut mounted on the second rail and a spindle operatively connected to the spindle nut are arranged in the inner channel, wherein a gear driveable by a motor and interacting with the spindle is arranged at one end of the first rail. The spindle nut is connected to the second rail by means of two crash bolts, wherein a circumferential gap is provided between each crash bolt and the second rail.

[0006] JP 2008-56 003 A discloses an electric seat sliding device comprising a lower rail and an upper rail, the upper rail being displaceable relative to the lower rail, a spindle rotatably mounted on an inner side of the upper rail, and a nut element screwed onto the spindle and fixed to the lower rail by two bolts. The two bolts are arranged in two through holes formed in the lower rail, with a clearance for movement of the bolts being formed between the bolts and a respective inner circumferential surface of the through hole.

[0007] DE 10 2008 024 141 A1 discloses a spindle bearing assembly for a seat length adjustment mechanism, which comprises a housing that can be fastened to a vehicle-side component or to a seat-side component by means of a fastening assembly. A spindle opening for passing a spindle through the housing extends along a spindle opening axis, and an internal thread is formed in the housing in the region of its spindle opening for engaging a spindle passed through in this way, for adjusting the housing and the spindle relative to one another along the spindle opening axis. The spindle bearing assembly provides that the internal thread is formed in a spindle nut, and the spindle nut is mounted in the housing so as to be adjustable relative to the spindle opening axis. Task

[0008] The invention is based on the object of improving a longitudinal adjuster of the type mentioned above, in particular, to provide a longitudinal adjuster whose spindle nut can be easily positioned in the longitudinal adjuster and is easy to install. Furthermore, a corresponding method for installing a longitudinal adjuster and a corresponding vehicle seat are also an underlying object. Solution

[0009] This object is achieved according to the invention by a longitudinal adjuster having the features of claim 1.

[0010] The longitudinal extension of the second rail preferably runs parallel to a longitudinal direction. The spindle nut is centered in a transverse direction by means of the two fixing elements. The spindle nut is preferably centered horizontally by means of the two fixing elements. When the longitudinal adjuster is used properly in a vehicle, the transverse direction preferably lies in a horizontal plane, provided the vehicle is traveling on a horizontal roadway.

[0011] The first rail is preferably a seat rail that can be connected to a vehicle seat. The second rail is preferably a floor rail that can be connected to a vehicle structure. A possible design of the spindle drive and its function are known, for example, from DE 10 2013 207 665 A1.

[0012] The spindle can be mounted at a front end portion of the spindle in the spindle gear and / or at a rear end portion of the spindle in a pivot bearing of the first rail.

[0013] The spindle nut can have a base body. The spindle nut can have a continuous threaded bore with an internal thread, particularly parallel to the longitudinal direction. The internal thread of the spindle nut can be operatively connected to an external thread of the spindle. The spindle is preferably screwed into the spindle nut. The spindle nut is preferably designed as a single piece.

[0014] The two fixing elements can each have a shaft with an external thread and a head section. The two fixing elements preferably have a cone between the shaft and the head section in a transition area between the shaft and the head section.

[0015] The first through-opening can have a substantially square cross-section with rounded corners. "Substantially square" within the meaning of the invention means that a slight difference of up to 1 millimeter in addition to a manufacturing tolerance, in particular up to 0.5 millimeters in addition to a manufacturing tolerance, is possible between a length and a width of the cross-section. The length is preferably measured in the longitudinal direction, and the width is preferably measured in the transverse direction.

[0016] The second through-opening can have a substantially rectangular cross-section with rounded corners. "Substantially rectangular" within the meaning of the invention means that a difference of at least 1 millimeter in addition to a manufacturing tolerance, in particular of at least 1.5 millimeters in addition to a manufacturing tolerance, is provided between a length and a width of the cross-section. The length is preferably measured in the longitudinal direction, and the width is preferably measured in the transverse direction.

[0017] The two through-openings can have the same dimensions perpendicular to the longitudinal extension of the second rail, in particular in the transverse direction. A dimension of the first through-opening parallel to the longitudinal extension of the second rail can be configured differently from a dimension of the second through-opening parallel to the longitudinal extension of the second rail. "Parallel to the longitudinal extension" is understood to mean, in particular, in the direction of the longitudinal extension.

[0018] The cone of the respective fixing element can have a diameter, in particular a maximum diameter, in a region adjacent to the respective head section, which is slightly larger than the dimension of the respective through opening perpendicular to the longitudinal extent, in particular in the transverse direction, of the second rail.

[0019] The dimension of the second through-opening in the direction of the longitudinal extension of the second rail can be larger than a diameter, in particular the maximum diameter, of the cone of the second fixing element. In the assembled state, a gap can be present in the longitudinal extension of the second rail in front of and / or behind the fixing element between the cone of the second fixing element and at least one edge portion of the second through-opening. The second fixing element can have a clearance in the second through-opening parallel to the longitudinal extension of the second rail.

[0020] For connection to the fixing elements, the spindle nut can each have a fixing opening. The inner diameter of the fixing opening is preferably adapted to the outer diameter of the fixing means. The fixing means can be a screw. The fixing means can be a bolt, in particular a threaded bolt.

[0021] A buffer can be arranged between the spindle nut, in particular the base body of the spindle nut, and the second rail. The buffer is preferably flat. The buffer can be made of a plastic, in particular a rubber. The buffer can be made of metal. The buffer can be made of metal on the one hand and plastic or rubber on the other. One side of the buffer can be made of metal and the other side of the buffer can be made of plastic and / or rubber.

[0022] The object is further achieved according to the invention by a method for assembling a longitudinal adjuster, in particular a longitudinal adjuster according to the above description, according to the features of claim 11.

[0023] Preferably, each of the two fixing elements has a cone in a transition area between a shaft and a head section. The two fixing elements can be configured identically.

[0024] The spindle nut can be arranged on the second rail with a buffer interposed. The buffer is preferably flat. The buffer can be made of a plastic, in particular rubber. The buffer can be made of metal. The buffer can be made of metal on the one hand and plastic or rubber on the other. One side of the buffer can be made of metal and the other side of the buffer can be made of plastic and / or rubber.

[0025] When the first fixing element is inserted into the first through-opening, the first fixing element can center itself in the first through-opening by means of the cone both parallel to a longitudinal extension of the second rail and perpendicular thereto, in particular in the transverse direction. When the second fixing element is inserted into the second through-opening, the second fixing element can center itself in the second through-opening by means of the cone, preferably exclusively perpendicular to the longitudinal extension of the second rail, in particular in the transverse direction.

[0026] The object is further achieved according to the invention by a vehicle seat with a previously described longitudinal adjuster.

[0027] In summary, and in other words, the spindle nut is typically attached to the lower rail using two to three screws in the prior art. The mounting holes in the lower rail for these screws are larger in diameter than the shank of the screw to compensate for tolerances and ensure a clean seat for the screw head. However, this requires active alignment of the spindle nut within the lower rail using additional receptacles during the screwing process.

[0028] According to the present invention, the screws for fastening the spindle nut can have a cone between the screw head and the shaft of the respective screw. This cone is preferably designed to ensure centering of the screw transversely to a corresponding through-hole in the bottom rail, regardless of all tolerances.

[0029] To ensure that the screw can be tightened all the way to the head contact, the through-hole can be designed so that the cone only comes into contact with an edge area of ​​the through-hole in the lower rail over a small contact area, in particular in a narrow section. This can be achieved using a rectangular hole which has approximately the same dimensions in the transverse direction of the lower rail as it does in the longitudinal direction. A second rectangular hole has a narrower dimension in the transverse direction of the lower rail and slightly larger in the longitudinal direction of the lower rail. This gives the second rectangular hole some play in the longitudinal direction to compensate for longitudinal tolerances. The small contact area allows the cone of the screw to deform the contact edge in the through-hole and the head surface of the screw to make secure contact. Figures and embodiments of the invention

[0030] The invention is explained in more detail below using an advantageous embodiment illustrated in the figures. However, the invention is not limited to this embodiment. They show: Fig. 1: a vehicle seat according to the invention, Fig. 2: a perspective view of a longitudinal adjuster according to the invention of the vehicle seat from Fig. 1 , Fig. 3: a perspective view of a pair of rails of the longitudinal adjuster from Fig. 2 , Fig. 4: a longitudinal section of the rail pair from Fig. 3 , Fig. 5: a partial exploded view of the pair of rails from Fig. 3 , wherein a second rail, a buffer, a spindle nut and two fixing elements are shown, Fig. 6: a partially sectioned view from above of the fixing elements arranged in the second rail, Fig. 7: a cross section through the spindle nut of the pair of rails from Fig. 3 , and Fig. 8: a partial enlargement of the representation of Fig. 4 in the area of ​​the spindle nut.

[0031] One in Figur 1 A schematically illustrated vehicle seat 1 is described below using three spatial directions running perpendicular to one another. In a vehicle seat 1 installed in the vehicle, a longitudinal direction x runs largely horizontally and preferably parallel to a vehicle longitudinal direction that corresponds to the normal direction of travel of the vehicle. A transverse direction y running 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 1 installed in the vehicle, the vertical direction z runs parallel to the vehicle's vertical axis. The longitudinal direction x and the transverse direction y can define a horizontal plane.

[0032] The position and direction specifications used, such as front, rear, top, and bottom, refer to the viewing direction of an occupant sitting in the vehicle seat 1 in a normal seating position, with the vehicle seat 1 installed in the vehicle, in a position suitable for passenger transport with the backrest 4 upright and oriented in the direction of travel as usual. However, the vehicle seat 1 can also be installed in a different orientation, for example, transverse to the direction of travel.

[0033] The Fig. 1 The vehicle seat 1 shown for a motor vehicle has a seat part 2 and a backrest 4 whose inclination can be adjusted relative to the seat part 2. The inclination of the backrest 4 can be adjusted, for example, by means of a locking fitting or a geared fitting. The vehicle seat 1 is mounted on a longitudinal adjuster 10 for adjusting the seat's longitudinal position.

[0034] Fig. 2 shows the longitudinal adjuster 10 according to the invention of the vehicle seat 1. The longitudinal adjuster 10 has at least one pair of rails, in this case two pairs of rails. Fig. 3 shows one of the rail pairs of the longitudinal adjuster 10.

[0035] The rail pairs are each formed from a first rail 12, in particular for connection to a seat structure of the vehicle seat 1, and a second rail 14, in particular for connection to a vehicle structure. The rails 12, 14 of the rail pair are displaceable relative to one another in the longitudinal direction x and alternately engage around one another to form an inner channel 16. A spindle nut 30, which is mounted on the second rail 14 and is arranged in a rotationally fixed manner in this case, and a spindle 20 operatively connected to the spindle nut 30 are arranged in the inner channel 16. The spindle 20 extends along a spindle axis S parallel to the longitudinal direction x. At a front end of the first rail 12, a spindle gear 70 is arranged, which can be driven by a motor 80 and drives the spindle 20. The motor 80 is held on a motor mount 90 mounted between the two spindle gears 70 of the respective rail pairs and drives the spindle 20 by means of a Fig. 2 The two spindle gears 70 are connected to a shaft not shown.

[0036] Fig. 4 shows a longitudinal section of the rail pair of Fig. 3 . The spindle gear 70 supports a front end section 20a of the spindle 20. The spindle nut 30 is arranged centrally along the length of the spindle 20 in the state shown here. By rotating the spindle 20 about the spindle axis S, the spindle nut 30 screws itself along an external thread of the spindle 20 in or against the longitudinal direction x, depending on the direction of rotation, and thereby displaces the first rail 12 relative to the second rail 14. In the process, a relative position between the spindle 10 and the spindle nut 30 also shifts accordingly. The spindle nut 30 has a through-threaded bore with an internal thread 32 parallel to the longitudinal direction x. The internal thread 32 of the spindle nut 30 can be operatively connected to an external thread of the spindle 20. The spindle nut 30 is designed as a one-piece in the present case.

[0037] The Figuren 5 bis 8show different views of a second rail 14 with a buffer 60, the spindle nut 30 and two fixing elements 40a, 40b.

[0038] The spindle nut 30 is designed as a single piece in the present case. The spindle nut 30 is fastened to the second rail 14 by means of the two fixing elements 40a, 40b. The spindle nut 30 is centered by means of the two fixing elements 40a, 40b perpendicular to a longitudinal extension of the second rail 14 relative to a respective through-opening 14a, 14b of the second rail 14, in particular a first through-opening 14a and a second through-opening 14b. The spindle nut 30 is centered horizontally by means of the two fixing elements 40a, 40b if the longitudinal extension of the second rail 14 runs parallel to the longitudinal direction x. The spindle nut 30 is centered by means of the two fixing elements 40a, 40b, in particular in the transverse direction y.

[0039] The spindle nut 30 has a fixing opening 34 for each of the fixing elements 40a, 40b. A buffer 60 is arranged between the second rail 14 and the spindle nut 30. The buffer 60 has a through-hole for each of the two fixing elements 40a, 40b. Edge regions of the through-holes of the buffer 60 are not necessarily in contact with the fixing elements 40a, 40b when assembled.

[0040] The first fixing element 40a and the second fixing element 40b are screws in this case. The first fixing element 40a and the second fixing element 40b are identical parts. The two fixing elements 40a, 40b each have a cone 46 in a transition area between a shaft 42 and a head portion 44. In this case, the shaft 42 of each fixing element 40a, 40b has an external thread.

[0041] The first through-opening 14a has, particularly prior to the assembly of the spindle nut 30 and the first fixing element 40a, a substantially square cross-section with rounded corners. The first fixing element 40a is arranged in the first through-opening 14a. Before the assembly of the spindle nut 30 and the first fixing element 40a, the dimension of the first through-opening 14a perpendicular to the longitudinal extent of the second rail 14, particularly in the transverse direction y, is slightly smaller than the largest diameter of the cone 46 of the first fixing element 40a in an area adjacent to the head portion 44 of the first fixing element 40a. In a state before the assembly of the first fixing element 40a, the dimension of the first through-opening 14a parallel to the longitudinal extension of the second rail 14 is equal to the dimension of the first through-opening 14a perpendicular to the longitudinal extension of the second rail 14, in particular in the transverse direction y.

[0042] During assembly of the spindle nut 30 and the first fixing element 40a, the cone 46 of the first fixing element 40a causes a slight deformation of the edge regions of the first through-opening 14a contacted by the cone 46. In the assembled state of the first fixing element 40a, the edge regions of the first through-opening 14a contacted by the cone 46 are deformed by displacement by the cone 46 such that the cone 46 of the first fixing element 40a comes into uniform contact with the edge regions of the first through-opening 14a and the head section 44 of the first fixing element 40a comes into secure contact with the second rail 14.

[0043] The second through-opening 14b has a substantially rectangular cross-section with rounded corners. The second fixing element 40b is arranged in the second through-opening 14b. Before the spindle nut 30 and the second fixing element 40b are mounted, the dimension of the second through-opening 14b perpendicular to the longitudinal extent of the second rail 14, in particular in the transverse direction y, is slightly smaller than the largest diameter of the cone 46 of the second fixing element 40b in an area adjacent to the head portion 44 of the second fixing element 40b. The dimension of the second through-opening 14b parallel to the longitudinal extent of the second rail 14 is larger than the largest diameter of the cone 46 of the second fixing element 40b.

[0044] Parallel to the longitudinal extension of the second rail 14, a clearance is provided between the second fixing element 40b and the edge regions of the second through-opening 14b.

[0045] During assembly of the spindle nut 30 and the second fixing element 40b, the cone 46 of the second fixing element 40b causes a slight deformation of the edge regions of the second through-opening 14b contacted by the cone 46, in particular the edge regions of the second through-opening 14b arranged laterally parallel to the longitudinal extent of the second rail 14. In the assembled state of the second fixing element 40b, the edge regions of the second through-opening 14b contacted by the cone 46 are deformed by displacement by the cone 46 in such a way that the cone 46 of the second fixing element 40b is aligned centrally between the contacted opposite edge regions of the second through-opening 14b and the head section 44 of the second fixing element 40b comes into secure contact with the second rail 14.

[0046] 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 the resulting subject matter falls within the scope of protection defined by the claims. List of reference symbols

[0047] 1Vehicle seat 2Seat part 4Backrest 10Length adjuster 12First rail 14Second rail 14aFirst through-hole 14bSecond through-hole 16Inner channel 20Spindle 20Front end section (of spindle 20) 20bRear end section (of spindle 20) 30Spindle nut 32Internal thread 34Fixing opening 40aFirst fixing element 40bSecond fixing element 42Shaft 44Head section 46Cone 60Buffer 70Spindle gear 80Motor 90Motor mount SSpindle axis (of spindle 20) xLongitudinal direction yTransverse direction zVertical direction

Claims

1. Longitudinal adjuster (10), having at least one pair of rails formed from a first rail (12) and a second rail (14), wherein the first rail (12) and the second rail (14), in particular in a longitudinal direction (x), are displaceable relative to each other, wherein the first rail (12) and the second rail (14), while forming an internal duct (16), mutually encompass each other, wherein disposed in the internal duct (16) are a spindle nut (30), connected to the second rail (14), and a spindle (20), operatively connected to the spindle nut (30), wherein disposed on the first rail (12) is a spindle drive (70) which is driveable by a motor (80) and interacts with the spindle (20), wherein the spindle nut (30) is fixed to the second rail (14) by a first fixing element (40a) and a second fixing element (40b), characterized in that the spindle nut (30) by the two fixing elements (40a, 40b) is centred perpendicularly to a longitudinal extent of the second rail (14) in a transverse direction (y), in that the first fixing element (40a) is fixed relative to a first through opening (14a), and the second fixing element (40b) is fixed relative to a second through opening (14b), wherein the first fixing element (40a) relative to the first through opening (14a), and the second fixing element (40b) relative to the second through opening (14b) are centred perpendicularly to the longitudinal extent of the second rail (14) in the transverse direction (y).

2. Longitudinal adjuster (10) according to Claim 1, wherein the first fixing element (40a) when being inserted into the first through opening (14a) is self-centred by a cone (46), both in a longitudinal direction (x) of the second rail (14) and perpendicularly thereto in a transverse direction (y).

3. Longitudinal adjuster (10) according to Claim 1 or 2, wherein the two fixing elements (40a, 40b) each have a shank (42), which has an external thread, and a head portion (44), wherein a transition region between the shank (42) and the head portion (44) has in each case one cone (46).

4. Longitudinal adjuster (10) according to any one of Claims 1 to 3, wherein the first through opening (14a) has a substantially square cross section with radiused corners.

5. Longitudinal adjuster (10) according to any one of Claims 1 to 4, wherein the second through opening (14b) has a substantially rectangular cross section with radiused corners.

6. Longitudinal adjuster (10) according to any one of Claims 1 to 5, wherein the dimensions of the two through openings (14a, 14b), perpendicular to the longitudinal extent of the second rail (14), are identical in the transverse direction (y).

7. Longitudinal adjuster (10) according to any one of Claims 3 to 6, wherein the cone (46) of the respective fixing element (40a, 40b) in a region contiguous to the respective head portion (44) has a diameter, wherein prior to assembling the fixing element (40a, 40b) the dimension of the respective through opening (14a, 14b), perpendicular to the longitudinal extent of the second rail (14), is slightly smaller in the transverse direction (y) than the diameter of the cone (46).

8. Longitudinal adjuster (10) according to any one of Claims 3 to 7, wherein the dimension of the second through opening (14b) in the direction of the longitudinal extent of the second rail (14) is larger than the diameter of the cone (46) of the second fixing element (40b).

9. Longitudinal adjuster (10) according to any one of Claims 1 to 8, wherein the second fixing element (40b) in the second through opening (14b) has a clearance in the direction of the longitudinal extent of the second rail (14).

10. Longitudinal adjuster (10) according to any one of Claims 1 to 9, wherein a buffer (60) is disposed between the second rail (14) and the spindle nut (30) .

11. Method for assembling a longitudinal adjuster (10), the method comprising the following method steps: a) providing a second rail (14), wherein the second rail (14) for fastening a spindle nut (30) has a first through opening (14a) and a second through opening (14b), b) disposing the spindle nut (30) on the second rail (14), c) inserting from a side of the second rail (14) that faces away from the spindle nut (30) a first fixing element (40a) through the first through opening (14a) into the spindle nut (30), d) inserting from a side of the second rail (14) that faces away from the spindle nut (30) a second fixing element (40b) through the second through opening (14b) into the spindle nut (30), characterized in that at least one of the two fixing elements (40a, 40b) in a transition region between a shank (42) and a head portion (44) has a cone (46), wherein the at least one fixing element (40a, 40b) when inserting the fixing element (40a, 40b) into the assigned through opening (14a, 14b) is self-centred by the cone (46), and the cone (46) of the fixing element (40a, 40b) deforms a contact edge of a peripheral region of the assigned through opening (14a, 14b).

12. Method according to Claim 11, wherein the inserting of the first fixing element (40a) and / or of the second fixing element (40b) comprises screwing into the spindle nut (30).

13. Vehicle seat (1) having a longitudinal adjuster (10) according to one of Claims 1 to 10.

14. Vehicle seat (1) according to Claim 13, wherein the longitudinal adjuster (10) is assembled according to a method according to either of Claims 11 or 12.