DE102016123836A1 - Seat for a motor vehicle with two pairs of rails - Google Patents

Abstract

The invention relates to a seat for a motor vehicle with two pairs of rails (1, 2), each consisting of a bottom rail (3, 4) for attachment to a vehicle floor, each a seat rail (5, 6) on which a seat frame is mounted , depending on an electric motor driven gear unit (8, 9), each with a threaded spindle and each coaxial with the threaded spindle mounted spindle nut, wherein at least one electric motor (M) is provided with reversible direction of rotation for simultaneous drive either the spindle nuts or threaded spindles and a the threaded spindles and the coaxial with this spindle nut a left-hand thread and the other of the threaded spindles and the coaxial with this spindle nut has a right-hand thread.

Description

The invention relates to a vehicle seat. Such seats are usually installed longitudinally adjustable in vehicles by the seat is on two pairs of rails. In each case a bottom rail (bolted to the vehicle floor) and a seat rail (carries the vehicle seat) form such a pair of rails. These can be electrically driven by a drivable gear unit - is provided consisting of threaded spindle and spindle nut. One of these gear elements is mounted on the bottom rail, the other on the seat rail and one of these gear elements is driven rotatably and the other rigidly mounted. Now, if the spindle nut or the threaded spindle is set in rotation by an electric motor, the seat moves in the vehicle longitudinal direction. Depending on the direction of rotation, the seat can move forward or backward.

It is common that the pairs of rails are not installed horizontally in the vehicle, but they are often installed with a forward - tilted upward position. This means that for a forward movement of the seat in the vehicle a much higher drive power is required, as for a backward (and down) movement in which the seat and body weight of the occupant helps support or the drive even acts braking.

Out DE19815283 A1 . DE10361874 A1 or DE102006022947 B3 Seats are known according to the preamble of claim 1. For threaded spindles and spindle nuts of both rail pairs, identical parts are used. Also EP0026582 A2 describes such a vehicle seat, wherein in each pair of rails, two threaded spindles and two spindle nuts can be arranged to increase the load capacity. If only one threaded spindle per pair of rails is used here, these are also identical parts. The common parts use is obvious, because of course you will use the same "screws" (threaded spindles), as far as possible. It comes a so-called "normal thread" (right-hand thread) used. This makes the seat cost-effective, which is of particular importance in the automotive industry. However, as has now been shown, the use of identical parts also has the consequence that no absolutely identical drive of the left and the right rail pair of a seat takes place, but this is not directly obvious. The usual rail profiles are asymmetrical and threaded spindles with the same thread pitch results in lateral forces that can point to the seat inside and one pair of rails to the seat outside with one pair of rails. Additional asymmetries may result from a rotational direction-dependent efficiency of reduction gears, which are used to drive the spindle nut / threaded spindle use. Ultimately results in a slightly different efficiency in the movement of the two pairs of rails. This may be negligible in the forward (upward) movement of the seat, but may be significant in the backward movement. A pair of rails can run heavier "downhill" than the other, which brings quality losses. It is an object of the invention to provide a vehicle seat, the rail pairs are operated with identical efficiency in order to improve the sense of quality in the operation of the seat.

At first surprising solution to this problem, an inventive seat on the features specified in claim 1. Further advantageous details of the invention will become apparent from the dependent claims.

Threaded spindles and associated spindle nuts of two pairs of rails of a seat according to the invention have a different thread pitch - on the one hand a right hand side and on the other hand a left hand thread. In this way, an absolute symmetry of the drive situation of both rail pairs can be produced. The solution can be driven by an electric motor regardless of whether spindle nuts or threaded spindles for the longitudinal adjustment of a seat.

In order to be able to move both seat rails of the pairs of rails forwards or both backwards, a drive with opposite direction of rotation also has to take place in the case of the aforementioned opposing thread pitches. As usual, gear units (consisting of threaded spindle and spindle nut) are driven by electric motor means of reduction gears. This reduction gear can be advantageously used to reverse the direction of rotation of a single direction of rotation of one or more electric motors. If two electric motors are provided, the direction of rotation reversal can alternatively also be generated by operating the two electric motors with different directions of rotation. In this case, the same reduction gear could be used.

As usual, worm gears can be used to drive the spindle nuts or the threaded spindles. In the case of the spindle nut drive drive screws can interact directly with an external toothing of the spindle nuts. In the case of the threaded spindle drive, the threaded spindles are connected at the end to a drive wheel, with which the drive screws can interact. In such reduction gears, the invention provides that the thread pitches of the screws of both rail pairs are opposite to each other and the Matching teeth of the spindle nut or the threaded spindle drive wheel are also executed opposite. This creates an identity in the drive situation and thus identical efficiencies in the movement of both seat rails in their bottom rails also in the field of reduction gears.

If a single electric motor is available for each pair of rails, identical reduction gears can be used for both rail pairs, and the opposite direction of rotation of both spindle nuts or two threaded spindles is achieved by simultaneous operation of the two electric motors in the opposite direction of rotation. As is well known, the spindle nuts or the threaded spindle drive wheels can be part of the reduction gears, but these then also differ from one another, depending on whether they are intended for one or the other pair of rails. It can be freely selected, which threaded spindles and associated reduction gear are selected in the left and right rail pair. Yes, after the selection is made, the efficiency of moving the seat rails will be slightly better when moving forward or backward. It is important that he is always the same for both pairs of rails. The pitch of the threads of the threaded spindles and the spindle nuts could be slightly different for the left and the right side of the seat can be selected to achieve certain effects - but preferably the slope should be selected identically, so that a synchronization of both rail pairs is expected. Only if the load on both pairs of rails is very different could the synchronization be adversely affected, which might be necessary to react to.

• 1: ein Sitz für ein Kraftfahrzeug gemäß der Erfindung;
• 2: eine Sitzschiene mit einer Getriebeeinheit nach dem Stand der Technik;
• 3: eine Sitzschiene mit einer anderen Getriebeeinheit nach dem Stand der Technik;
• 4: zwei Schienenpaare des Sitzes nach 1 in perspektivischer Ansicht;
• 5: die Schienenpaare nach 4 in einer Frontansicht;
• 6: ein Schnitt durch die Getriebeeinheiten der Schienenpaare nach 5;
• 7: eine Getriebeeinheit eines tunnelseitigen Schienenpaares in zwei Ansichten;
• 8: eine Getriebeeinheit eines türseitigen Schienenpaares in zwei Ansichten.

In the following the invention will be explained with reference to an embodiment. From the accompanying drawings shows:

• 1 a seat for a motor vehicle according to the invention;
• 2 a seat rail with a transmission unit according to the prior art;
• 3 a seat rail with another transmission unit according to the prior art;
• 4 : two seat pairs of seat behind 1 in perspective view;
• 5 : the rail pairs behind 4 in a front view;
• 6 : a section through the gear units of the rail pairs after 5 ;
• 7 a gear unit of a tunnel-side rail pair in two views;
• 8th : a gear unit of a door-side rail pair in two views.

The in 1 shown in an overview seat has two pairs of rails 1 . 2 on. A rail pair 1 is door side and a pair of rails 2 arranged on the tunnel side in a motor vehicle. The rail pairs 1 . 2 each consist of a bottom rail to be fastened to a vehicle floor 3 . 4 and a seat rail 5, 6 displaceably guided thereon, on which a seat frame 7 is stored. As usual, the seat is due to the arrangement on the rail pairs 1 . 2 slidably mounted in the vehicle longitudinal direction.

From the prior art ( 2 and 3 ) is known to be seat rails 5 . 6 electrically relative to ground rails 3 . 4 be adjusted. For this purpose, rigidly arranged threaded spindles are combined with motor-driven spindle nuts, or rigidly arranged spindle nuts are combined with rotationally drivable threaded spindles. The threaded spindles can either be attached to a bottom rail 3 . 4 or on a seat rail 5 . 6 are arranged and the spindle nuts are mounted on the other rail. 2 shows a conventional arrangement with driven spindle nut and 3 shows a likewise common version with driven threaded spindle. The driven element should be illustrated in each case by the arrows indicating a rotation. In both versions, each driven element is mounted on the seat rail - so it moves with a seat frame 7 with - and the rigidly mounted element of the gear unit is attached to the bottom rail. Thus, the respectively driven element and an electric motor provided for the drive moves with the seat frame. However, embodiments are also conceivable in which this is reversed: the driven threaded spindle or the driven spindle nut can also be attached to the bottom rail and then does not move with the seat frame.

From the following figures, the specific design of gear units results 8th . 9 , each consisting of a threaded spindle 10 . 11 and from a spindle nut 12 . 13 consist. In the embodiment, the two spindle nuts 12 . 13 driven by an electric motor M. As in particular from the 7 and 8th becomes clear, the threaded spindles 10,11 and the associated spindle nuts 12 . 13 equipped with a thread which is opposite on the door side to the one on the tunnel side. Door side is a right-hand thread in the threaded spindle 10 and the spindle nut 12 provided and tunnel side are left-hand thread on the threaded spindle 11 and the spindle nut 13 appropriate. Crucial to the invention is that two pairs of rails 1, 2, which mirror-symmetrically under a seat frame 7 are arranged, mirror-symmetrical gear units 8,9 are assigned, so that the balance of power when moving the seat rails 5 . 6 relative to the bottom rails 3,4 are identical. This advantage is compared with only a small additional expenditure, which results from the fact that two types of threaded spindles 10 . 11 and spindle nuts 12 . 13 held and must be installed free of confusion. As an electric motor drive for the spindle nuts 13, 13 (as in the embodiment) or for the threaded spindles (not driven) is one or two usual per se electric motors M used whose speed as usual by reduction gear 14 . 15 is to be reduced. Because the threads of the threaded spindles 10 . 11 and the spindle nuts 12 . 13 Now in opposite directions, both would be seat rails 5 . 6 move opposite to each other with the same drive direction, which of course should not be. That's why the reduction gears 14 . 15 also be designed so that at the same drive direction of rotation opposite rotation of the spindle nuts 12 . 13 results. However, if a separate electric motor M is provided for each spindle nut, the same reduction gear can be used and the two motors M are, however, operated in the opposite direction of rotation (not shown here). In the embodiment, the reduction gear 14 . 15 as usual in unit with the gear units 8th . 9 intended. The coaxial with the threaded spindles 10 . 11 arranged and meshing with their thread spindle nuts 12 . 13 have on their outer circumference on a helical toothing, which with the teeth of a respective (driven during a seat-length adjustment) drive screw 16 . 17 combs. These teeth are opposite the door and tunnel (mirror symmetry) formed, resulting in an opposite direction of rotation results in the same drive direction of a motor shaft. Should the reduction gear 14 . 15 have a slightly depending on the direction of rotation different efficiency is ensured so that even in the distribution of the driving force on the door and tunnel-side gear units 8th . 9 always identical efficiencies exist.

An exchange of gear units 8,9 and the reduction gear 14 . 15 between the door and the tunnel side of the seat is of course possible, because this would not change the efficiency of the movement of the seat rails 5 . 6 is identical.

Will not - as shown in the embodiment - the spindle nuts 12 . 13 driven by electric motor, but the threaded spindles are to be driven, this can be implemented comparable to the embodiment. At one end of each threaded spindle, as usual, a drive wheel is fixedly mounted and these drive wheels can via reduction gear - comparable to the reduction gears 14 . 15 ) - are driven. Again, then identical efficiencies result when adjusting the left and right rail pair 1 . 2 ,

Theoretically, it is still conceivable, the slopes of the threads of the spindle nuts 12 . 13 and to make the threaded spindles 10,11 on the one seat side slightly different from the pitches of the threads on the other side of the seat. So you could compensate for different motion load conditions on the left and right side of the seat. This would be the advantage of an identical efficiency but again partially abandon, which is why the same thread pitches are preferred left and right. With the invention it is achieved that with little additional effort a drive of both rail pairs 1 . 2 a seat with absolutely identical efficiency can be done. Thus, under certain conditions of use of the seat quality and comfort advantages can be achieved.

LIST OF REFERENCE NUMBERS

1

Rail pair on the door side

2

Rail pair on the tunnel side

3

Bottom rail of 1

4

Bottom rail of 2

5

Seat rail from 1

6

Seat rail of 2

7

seat frame

8th

Gear unit on the door side

9

Gear unit on the tunnel side

10

Threaded spindle on the door side

11

Threaded spindle on the tunnel side

12

Spindle nut on the door side

13

Spindle nut on the tunnel side

14

Reduction gear door side

15

Reduction gear tunnel side

16

Drive screw on the door side

17

Drive screw on the tunnel side

QUOTES INCLUDE IN THE DESCRIPTION

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

Cited patent literature

• DE 19815283 A1 [0003]
• DE 10361874 A1 [0003]
• DE 102006022947 B3 [0003]
• EP 0026582 A2 [0003]

Claims (8)

Seat for a motor vehicle with two pairs of rails (1, 2), consisting of a. each a bottom rail (3, 4) for attachment to a vehicle floor, b. a respective seat rail (5, 6), which is displaceably mounted in each floor rail (3, 4) and on which a seat frame (7) is mounted, c. each of an electric motor driven gear unit (8, 9), with i. depending on a rigid or rotatable on the bottom rail (3, 4) or the seat rail (5, 6) mounted threaded spindle (10, 11), ii. depending on the seat rail (5, 6) or the bottom rail (3, 4) coaxially with the threaded spindle (10, 11) mounted spindle nut (12, 13), with a with the threaded spindle (10, 11) meshing internal thread, d. at least one electric motor (M) with reversible direction of rotation for simultaneous drive either the spindle nuts (12, 13) or the threaded spindles (10, 11), characterized in that one of the threaded spindles (11) and the spindle nut (13) coaxial therewith a left-hand thread and the other of the threaded spindles (10) and the coaxial with this spindle nut (12) has a right-hand thread and that the spindle nuts (12, 13) or the threaded spindles (10, 11) of the two rail pairs (1, 2) for seat longitudinal adjustment with opposite direction of rotation are driven. Seat after Claim 1 , characterized in that a reduction gear is provided as part of the transmission unit, through which a speed of the electric motor, which is transmitted to a spindle nut or on a spindle, is reduced. Seat after Claim 2 , characterized in that the opposite direction of rotation of the spindle nuts (12, 13) or the threaded spindles (10, 11) by different reduction gear (14, 15) is generated. Seat after Claim 3 , characterized in that the reduction gears (14, 15) are worm gears, in each case a worm (16, 17) of the electric motor (M) is driven and a toothing of the worm (16, 17) with an external toothing of the respective spindle nut ( 12, 13) meshes, wherein the reduction gear (14, 15) opposite pitches of the screws (16, 17) and thus corresponding external teeth of the spindle nuts (12, 13). Seat after Claim 3 , characterized in that the reduction gears are worm gears, in each of which a worm is driven by the electric motor and a toothing of the worm meshes with an external toothing of a threaded drive wheel, wherein the reduction gear opposite inclinations of the worm and thus having external teeth of threaded spindle drive wheels , Seat after Claim 2 , characterized in that the opposite direction of rotation of the spindle nuts (12, 13) or the threaded spindles (10, 11) is generated in each case by use of an electric motor (M) per pair of rails by simultaneous operation of the two electric motors in the opposite direction of rotation. Seat after one of the Claims 2 to 6 , characterized in that drivable spindle nuts (12, 13) with on the one hand left and on the other hand right internal thread or drivable threaded spindle drive wheels are part of the reduction gear (14, 15) and each one of these reduction gear (14, 15) per pair of rails (1, 2) is installed. Seat after at least one of the Claims 1 to 7 , characterized in that a slope of the left and right threads of the threaded spindles (10, 11) and the spindle nuts (12, 13) is the same.

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