CN221137766U - Seat frame for a vehicle seat and vehicle seat - Google Patents

Abstract

The present utility model relates to a seat frame for a vehicle seat and a vehicle seat. The seat frame includes a base to be fixed to a floor of the vehicle, a seat frame located above the base, a front link having one end pivotally connected to a front side of the seat frame, a rear link having one end pivotally connected to a rear bracket at an upper portion of the base and the other end pivotally connected to a rear side of the seat frame, and a height adjustment mechanism driving the rear link to rotate about a pivot point thereof with the base. The seat frame is movable to a fully upward position by the height adjustment mechanism. According to the utility model, the seat frame can also be moved to an additional forward position in which the seat frame is further forward than in the fully upward position. The vehicle seat comprises the seat frame. The vehicle seat can realize a convenient entering function by utilizing the height adjusting mechanism of the seat, and additional parts are not required to be additionally arranged.

Description

Seat frame for a vehicle seat and vehicle seat

Technical Field

The present utility model relates to the field of vehicles. In particular, in a first aspect, the present utility model relates to a seat frame for a vehicle seat (e.g., a zero gravity vehicle seat). In a second aspect, the utility model relates to a vehicle seat (e.g., a zero gravity vehicle seat) comprising the seat frame.

Background

In recent years, zero gravity seats have been increasingly used in vehicles because of their advantage of being able to maximize the comfort of the occupants. Such vehicle seats generally employ five-bar linkages (one on each side of the seat) to achieve recline and height adjustment of the seat to meet the requirements of a zero-gravity seat for occupant adjustment of the seat attitude. The five-bar linkage is composed of a front bar, a seat frame, a rear bar (height adjusting bar) and a base, and a reclining bar, wherein the front portion has three pivot points, one end of the front bar is pivotally connected to the seat frame, the other end is pivotally connected to one end of the reclining bar, the other end of the reclining bar is pivotally connected to the base, wherein the rear portion has two pivot points, the rear bar is connected to the pivot points of the two rear portions, and wherein the pivot point of the lower portion is fixed to the base, and the rim of the seat frame is connected to the pivot point of the upper portion.

The height adjustment and the tilt adjustment of the zero-gravity vehicle seat are controlled, for example, by two rotary drive mechanisms, only one of which is active at a time, the other being in a self-locking state for switching between the height adjustment and the tilt adjustment. When the height adjustment is performed, the rotation driving mechanism associated with the rear link is operated to drive the rear link to rotate (at this time, the reclining link is locked, and thus the rear link, the seat frame, the front link, and the base constitute a four-bar mechanism), thereby adjusting the seat frame height. When the recliner is adjusted, the rotational drive mechanism associated with the front link operates to drive the recliner link about its pivotal connection point with the base to rotate the seat frame about the upper rear pivot point (at which point the rear link is locked so the seat frame cannot rotate about the lower rear pivot point) thereby adjusting the recliner angle of the seat frame.

In addition, in order to synchronize the movement of both sides of the zero gravity vehicle seat, the front and rear parts of the seat are respectively provided with a synchronizing rod, wherein both ends of the synchronizing rod at the front part are respectively and fixedly connected at the pivot connection point of the front connecting rod and the tilt adjusting connecting rod, and both ends of the synchronizing rod at the rear part are respectively and fixedly connected at the pivot connection point of the rear connecting rod and the seat frame.

To facilitate ingress and egress of rear passengers, some vehicle seats are equipped with a convenient entry (EASY ENTRY) function. When a rear passenger enters, the seat back is rotated forward by a certain angle and the seat is moved forward by a certain distance so as to make enough space for the rear passenger to enter the vehicle.

The current easy entry function is basically implemented based on a slide lock/unlock mechanism (for a manual vehicle seat) or a latch mechanism (for an electric vehicle seat) that is attached to the vehicle seat. On the one hand, in order to make room for the rear passengers to enter, the existing mechanisms are heavy and complex in structure. On the other hand, these added mechanisms introduce additional parts (e.g., slide locking/unlocking structures, latch mechanisms) that increase the cost of manufacturing the vehicle seat.

Disclosure of Invention

It is an object of the present utility model to provide a vehicle seat, such as a zero gravity vehicle seat, with a convenient entry function while avoiding the above-mentioned drawbacks present in existing vehicle seats. Therefore, the utility model provides a vehicle seat with a convenient access function, such as a zero-gravity vehicle seat, which can realize convenient access by utilizing a height adjusting mechanism of the seat, and no additional parts are required to be additionally arranged.

In one aspect, the present utility model provides a seat frame. The seat frame includes a base to be fixed to a floor of a vehicle, a seat frame located above the base, a front link having one end pivotally connected to a front side of the seat frame, a rear link having one end pivotally connected to a rear bracket at an upper portion of the base and the other end pivotally connected to a rear side of the seat frame, and a height adjusting mechanism driving the rear link to rotate about a pivot point thereof with the base. The seat frame is movable to a fully upward position by the height adjustment mechanism. According to the utility model, the seat frame can also be moved to an additional forward position in which the seat frame is further forward than in the fully upward position.

The invention is conceived to use the height adjustment mechanism of the seat to provide additional forward pivotal movement of the seat, thereby creating more space to provide easy entry.

According to an embodiment, in the additional forward position the seat frame is 70-100mm forward than in the fully upward position, for example by pivoting the front and rear links further forward.

According to an embodiment, the seat frame further comprises a recliner mechanism for adjusting the tilt of the seat frame.

According to an embodiment, the inclination adjusting mechanism comprises an inclination adjusting connecting rod, the other end of the front connecting rod is hinged with one end of the inclination adjusting connecting rod, and the other end of the inclination adjusting connecting rod is pivotally connected with a front side bracket at the upper part of the base; and a tilt drive mechanism that drives the tilt adjustment link in rotation about its pivot point with the base.

According to an embodiment, the reclining drive mechanism includes a spindle motor arranged in a direction perpendicular to a seat front-rear direction; and a screw engaged with an output end of the spindle motor, wherein the spindle motor is disposed on the tilt adjusting link, one end of the screw is disposed on a front side bracket at an upper portion of the base, and wherein rotation of the output end of the spindle motor causes the spindle motor to move along the screw, driving the tilt adjusting link to rotate about a pivot point thereof with the base.

According to another embodiment, the reclining mechanism includes a spindle motor disposed along a seat front-rear direction; and a screw engaged with an output end of the spindle motor, wherein the spindle motor is disposed on a front side of a rim of the seat frame, and one end of the screw is disposed on a front side bracket at an upper portion of the base, wherein rotation of the output end of the spindle motor causes it to move along the screw, whereby the spindle motor and the screw constitute a front link of adjustable length, wherein a length of the front link is adjusted by a stroke length of the spindle motor along the screw.

According to still another embodiment, the other end of the front link is pivotally connected to a front side bracket at the upper portion of the base so that the height adjustment mechanism also functions as a reclining mechanism by which the seat frame is reclined back and down. In this embodiment, the seat frame may comprise a seat pan on the front side which can be tilted upwards relative to the rim of the seat frame, for example by means of a further tilt angle adjustment mechanism, wherein the tilt angle of the seat frame is further adjusted by adjusting the tilt angle of the seat pan. For example, the seat pan may be tilted up 10 degrees relative to the bezel. In this embodiment, the seat frame is tilted backward and downward, for example, 8 degrees, by the height adjustment mechanism. Thus, the seat frame can obtain a total tilt angle of 18 degrees, thereby achieving a zero gravity state. In this embodiment, the seat frame may not include any reclining mechanism on the front side, so that the reclining angle of the seat frame is adjusted only by the height adjustment mechanism to achieve the zero gravity state.

According to an embodiment, the height adjusting mechanism includes a spindle motor arranged in the seat front-rear direction; and a screw engaged with an output end of the spindle motor, wherein the spindle motor is disposed on the rear link, and one end of the screw is disposed on a rear bracket at an upper portion of the base, such that rotation of the output end of the spindle motor causes movement thereof along the screw, driving the rear link to rotate about its pivot point with the base.

According to another embodiment, the height adjustment mechanism includes a height drive motor that is arranged in the seat front-rear direction; the driving gear is in transmission connection with the output shaft of the motor; and a rack engaged therewith, wherein the rack is provided on the rear link, and the motor and the drive gear are provided on the rear side of the bezel of the seat frame.

In embodiments where the tilt/height adjustment mechanism includes a spindle motor, the limit of travel of the spindle motor along the lead screw is set by providing a stop or by an electronic control unit.

Preferably, the seat framework further comprises a front synchronizing rod for synchronizing the inclination adjustment movements of the two sides of the seat, wherein the two ends of the front synchronizing rod are respectively and fixedly connected to the pivot connection points of the base and the inclination adjustment connecting rod on the left side and the right side of the seat framework.

Preferably, the left side and the right side of the seat framework are provided with inclination angle adjusting mechanisms and/or height adjusting mechanisms. With this arrangement, the effort that adjustment mechanism bore can be dispersed, adjustment mechanism's stability is improved to can select for use less drive unit or motor, reduce seat cost. It is also possible for the seat frame to be provided with a tilt adjustment mechanism and/or a height adjustment mechanism on only one side, i.e. only one drive motor or spindle motor.

According to the embodiment, the base is of a slide rail structure, and the seat frame can slide along the slide rail along with the inclination angle adjusting mechanism and the height adjusting mechanism through the front-rear driving mechanism so as to realize front-rear adjustment of the seat.

In another aspect, the present utility model also provides a vehicle seat, such as a zero gravity vehicle seat, comprising a seat frame as described above.

The vehicle seat (such as a zero-gravity vehicle seat) can generate extra space by utilizing the height adjusting mechanism of the seat, so that a convenient entering function is realized, a rear passenger can enter the vehicle conveniently, and the defects of increased manufacturing cost and complex and heavy structure caused by adding extra parts are avoided.

Drawings

Embodiments of the present utility model will be explained in more detail in the accompanying drawings, in which:

Fig. 1 is a schematic view of a zero gravity vehicle seat frame in a convenient entry position in accordance with an embodiment of the utility model.

FIG. 2 is a schematic illustration of a zero gravity vehicle seat frame in a zero gravity position in accordance with an embodiment of the utility model.

Fig. 3A-3F are schematic diagrams of a zero gravity vehicle seat frame performing a easy entry sequence according to an embodiment of the utility model, wherein fig. 3A shows the seat in an initial position, fig. 3B shows the back rotated to a fully forward position, fig. 3C shows the back rotated to a fully forward position and the seat frame in a fully upward position, fig. 3D shows only the seat frame in an additional forward position, fig. 3E shows the back rotated to a fully forward position and the seat frame in an additional forward position, and fig. 3F shows the seat in a fully forward position (i.e., in an easy entry position).

Fig. 4 is a schematic view of a zero gravity vehicle seat frame in a convenient entry position in accordance with another embodiment of the utility model.

Fig. 5 is a schematic view of a zero gravity vehicle seat frame in a zero gravity attitude in accordance with another embodiment of the utility model.

Fig. 6 is a schematic view of a zero gravity vehicle seat frame in a convenient entry position in accordance with yet another embodiment of the utility model.

Fig. 7 is a schematic view of a zero gravity vehicle seat frame in a zero gravity attitude in accordance with yet another embodiment of the utility model.

The figures are not necessarily drawn to scale. In the drawings, like reference numerals refer to like parts.

Detailed Description

Hereinafter, an embodiment of the present utility model is described with reference to fig. 1 to 7. For ease of description, directional terminology is used below with reference to the orientation of a vehicle seat when installed in a vehicle.

Fig. 1 and 2 show a seat frame 100 according to a first embodiment of the present utility model. The seat frame 100 includes a base 110 to be fixed to a vehicle floor (not shown), a seat frame 120 located above the base 110, a front link 130 having one end pivotally connected to a front side of the seat frame 120 and the other end hinged to a reclining link 161, a rear link 140 having one end pivotally connected to a rear bracket 111 of an upper portion of the base 110 and the other end pivotally connected to a rear side of the seat frame 120, a height adjustment mechanism 150 driving the rear link 140 to rotate about its pivot point with the base 110, and a reclining mechanism 160 adjusting a reclining angle of the seat frame 120.

The base 110 is of a slide rail construction such that the seat frame 120 can slide along the slide rail with the reclining mechanism 160 and the height adjustment mechanism 150 by a front-rear drive mechanism 113 (e.g., a drive motor) to achieve front-rear adjustment of the seat.

The height adjusting mechanism 150 includes a spindle motor 151 disposed in the front-rear direction of the seat 100; and a screw 152 engaged with an output end of the spindle motor 151, wherein the spindle motor 151 is disposed on the rear link 140, and one end of the screw 152 is disposed on the rear bracket 111 at an upper portion of the base 110, such that rotation of the output end of the spindle motor 151 causes it to move along the screw 152, which in turn drives the rear link 140 to rotate about its pivot point with the base 110.

The tilt angle adjusting mechanism 160 comprises a tilt angle adjusting connecting rod 161, the other end of the front connecting rod 120 is hinged with one end of the tilt angle adjusting connecting rod 161, and the other end of the tilt angle adjusting connecting rod 161 is pivotally connected with a front side bracket 112 at the upper part of the base 110; and a tilt drive mechanism that drives rotation of tilt adjustment link 161 about its pivot point with base 110. The reclining drive mechanism includes a spindle motor 162 arranged in a direction perpendicular to the front-rear direction of the seat 100; and a screw 163 engaged with an output end of the spindle motor 162, wherein the spindle motor 162 is disposed on the tilt link 161, and one end of the screw 163 is disposed on the front side bracket 112 at an upper portion of the base 110, wherein rotation of the output end of the spindle motor 162 causes it to move along the screw 163, which in turn drives the tilt link 161 to rotate about its pivot point with the base 110.

In this example, the seat frame 100 is provided with tilt drive mechanisms on both left and right sides, i.e., one spindle motor 162 and screw 163 are provided twice, but is provided with only one side or height adjustment mechanism 150, i.e., only one spindle motor 151 and screw 152.

Fig. 1 and 2 also show a backrest 190, which can be adjusted by means of a recliner 191.

In addition, the seat frame 100 further includes a front synchronizing bar 170 for synchronizing the reclining motions of both sides of the seat frame 100, and both ends of the front synchronizing bar 170 are fixedly connected to pivot connection points of the base 110 and the reclining link 161 of the left and right sides of the seat frame 100, respectively. The seat frame 100 further includes a rear cross pipe 180 that connects the rear links 140 at the left and right sides to synchronize the height adjustment motions at both sides of the seat frame 100.

The limits of travel of the spindle motors 151, 162 along the associated lead screws 152, 163 are set by providing stops or by an electronic control unit to define the additional forward position of the seat frame in the easy entry attitude and the tilt angle of the seat in the zero gravity attitude, respectively. Further, by setting the engagement positions of the spindle motor and the associated lead screw, the forward-most position and the rearward-most position of the reclining link and the front-rear link, respectively, in the seat in the initial position can be defined.

In fig. 1, the seat is in a easy entry position (fully forward position, see fig. 3F) in which the front and rear links are rotated forward by the height adjustment mechanism such that the seat frame is moved to an additional forward position (see fig. 3D and 3E), while the seat is moved to the fully forward position along the slide rails by the front and rear drive mechanism and the backrest is rotated forward to an angle by the recliner to achieve the easy entry position.

The sequence of execution of the easy entry function of the seat frame 100 is shown in fig. 3A-3F, wherein only the height adjustment mechanism is activated and the recliner link is in a locked state such that the rear link, seat frame, front link, and base form a four-bar mechanism. Fig. 3A shows the seat frame in an initial position in which the front and rear links are rotated to the rearmost position and the recliner links are rotated to the forwardmost position such that the seat frame is in the lowermost position. The backrest is then rotated to the fully forward position by the recliner as shown in figure 3B. In an alternative embodiment, instead of rotating the backrest to the fully forward position, the front and rear links are rotated forward by the height adjustment mechanism to move the seat frame to the fully upward position (not shown). After fig. 3B, the front and rear links are rotated forward by the height adjustment mechanism, which moves the seat frame to the fully up position, as shown in fig. 3C. Or in the alternative embodiment described above, the front and rear links are rotated further forward by the height adjustment mechanism, as shown in fig. 3D, bringing the seat frame to an additional forward position in which the seat frame is 70-100mm forward than in the fully upward position, by increasing the limit of travel of the spindle motor of the height adjustment mechanism along the lead screw (e.g. using a longer lead screw), which can be set by setting a stop or by an electronic control unit. The seat frame is then moved to an additional forward position (next to fig. 3C) or the backrest is rotated to a fully forward position (next to fig. 3D), as shown in fig. 3E. Thereafter, the seat frame is moved to the fully forward position (i.e., in the easy entry position) by the front-rear drive mechanism, as shown in fig. 3F.

In fig. 2, the seat is in a zero gravity position, wherein the recliner link and the rear link are rotated rearward by the recliner drive mechanism such that the seat frame is tilted downward from front to rear and the back is rotated rearward to an angle by the recliner to achieve the zero gravity position. During this time, only the tilt drive mechanism is activated, while the rear link is in the locked state.

Fig. 4 and 5 show a seat frame 200 according to a second embodiment of the present utility model. Similar to the first embodiment, the seat frame 200 includes a base 210, a seat frame 220, a rear link 240 having one end pivotally connected to a rear bracket 211 at an upper portion of the base 210 and the other end pivotally connected to a rear side of the seat frame 220, a height adjustment mechanism 250, and a reclining mechanism 260. The seat frame also includes a rear cross tube (not shown), a back 290 and a recliner 291. Reference may be made specifically to the first embodiment, and details are not repeated here.

Unlike the first embodiment, the reclining mechanism 260 includes a spindle motor 262 that is arranged in the seat front-rear direction; and a screw 263 engaged with an output end of the spindle motor 262, wherein the spindle motor 262 is disposed on a front side of a rim of the seat frame 220, and one end of the screw 263 is disposed on a front side bracket 212 of an upper portion of the base 210 such that rotation of the output end of the spindle motor 262 causes it to move along the screw 263, whereby the spindle motor 262 and the screw 263 constitute a single link with an adjustable length, which serves as the front link 230, and wherein the length of the front link 230 is adjusted by a stroke length of the spindle motor 262 along the screw 263, thereby adjusting an inclination angle of the seat frame 220.

Further, in this example, the height adjustment mechanism 250 includes a height drive motor 251 that is arranged along the front-rear direction of the seat frame 200; a drive gear 252 in driving connection with the motor output shaft; and a rack (not shown) engaged therewith, wherein the rack is provided on the rear link 240, and the height driving motor 251 and the driving gear 252 are provided on the bezel rear side of the seat frame 220.

Similar to fig. 1, in fig. 4, the seat is in a convenient entry position. As in the first embodiment, the front and rear links are rotated forward by the height adjustment mechanism so that the seat frame is moved to the additional forward position, while the seat is moved to the full forward position along the slide rail by the front and rear drive mechanism and the backrest is rotated forward to an angle by the recliner so as to achieve the easy entry posture. During this time, only the height adjustment mechanism is activated, while the reclining mechanism is not activated.

Similar to fig. 2, in fig. 5, the seat is in a zero gravity position. But unlike the first embodiment, the length of the front link is increased by the reclining mechanism (spindle motor 262 and screw 263) to rotate the front and rear links rearward therewith, so that the seat frame is tilted downward from front to rear, and the backrest is rotated rearward to an angle by the recliner to achieve the zero gravity posture. During this time, only the reclining mechanism is activated, while the height adjustment mechanism is not activated.

Fig. 6 and 7 show a seat frame 300 according to a third embodiment of the present utility model. Similar to the first embodiment, the seat frame 300 includes a base 310, a seat frame 320, a front link 330 having one end pivotally connected to a front side of the seat frame 320, a rear link 340 having one end pivotally connected to a rear bracket 311 at an upper portion of the base 310 and the other end pivotally connected to a rear side of the seat frame 320, and a height adjustment mechanism 350. The seat frame also includes a rear cross tube (not shown), a backrest 390 and a recliner 391. The height adjustment mechanism 350 includes a spindle motor 351 and a lead screw 352. Reference may be made specifically to the first embodiment, and details are not repeated here.

Unlike the first embodiment, the other end of the front link 330 is pivotally connected to the front side bracket 312 of the upper portion of the base 310, and the seat frame 320 includes a seat pan 321 capable of tilting upward with respect to the rim of the seat frame 320 at the front side, and the reclining mechanism 360 adjusts the tilt angle of the seat frame 320 by adjusting the tilt angle of the seat pan 321.

In this example, the seat pan 321 can tilt up 10 degrees relative to the bezel. In addition, by setting the height adjustment mechanism 350 so that the rear link 340 can be further rotated rearward from the initial position, the seat frame 320 is tilted downward from front to rear by 8 degrees. Thus, the seat frame 320 can obtain a total tilt angle of 18 degrees, so that the seat frame 300 reaches a zero gravity posture.

Similar to fig. 1, in fig. 6, the seat is in a convenient entry position. As in the first embodiment, the front and rear links are rotated forward by the height adjustment mechanism so that the seat frame is moved to the additional forward position, while the seat is moved to the full forward position along the slide rail by the front and rear drive mechanism and the backrest is rotated forward to an angle by the recliner so as to achieve the easy entry posture. During this time, only the height adjustment mechanism is activated, while the reclining mechanism is not activated.

In fig. 7, the seat is in a zero gravity position. Unlike the first embodiment, the seat pan is tilted upward by 10 degrees with respect to the bezel by the reclining mechanism, while the front and rear links are rotated rearward by the height adjustment mechanism such that the seat frame is tilted downward by 8 degrees from front to rear, thereby making the seat frame acquire a total tilt angle of 18 degrees, and the backrest is rotated rearward by the recliner to an angle such that the zero gravity posture is achieved.

The third embodiment is lower in manufacturing cost than the first and second embodiments.

In the third embodiment, in addition to the reclining mechanism 360, the height adjustment mechanism 350 also functions as a reclining mechanism. For example, by setting the height adjustment mechanism such that the height adjustment mechanism enables additional rearward tilting movement of the seat frame to achieve a zero gravity condition, compared to the lowest position of the seat frame in the first and second embodiments, without the need for the tilt adjustment mechanisms of the first and second embodiments.

It is conceivable that in the third embodiment, the tilt angle of the seat frame is adjusted only by the height adjusting mechanism to achieve the zero gravity state, while the seat frame does not include any tilt angle adjusting mechanism on the front side.

In some cases, features disclosed herein may be used independently of other features. On the other hand, the features disclosed herein can be combined, when necessary, to provide various combinations.

The phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting. For example, while the above-described embodiments are based on a zero-gravity vehicle seat, the present utility model may be applied to other types of vehicle seats, i.e., vehicle seats without a zero-gravity function. Therefore, the present utility model is not limited to the above-described embodiments. Moreover, it is obvious to a person skilled in the art that the basic idea of the utility model can be implemented in various ways. Accordingly, various modifications, adaptations, and alternatives are possible within the scope of the claims.

Claims (15)

1. A seat frame for a vehicle seat, the seat frame comprising a base to be secured to a vehicle floor, a seat frame located above the base, a front link pivotally connected at one end to a front side of the seat frame, a rear link pivotally connected at one end to a rear side bracket of an upper portion of the base and at the other end to a rear side of the seat frame, and a height adjustment mechanism driving the rear link to rotate about its pivot point with the base, wherein the seat frame is movable to a fully up position by the height adjustment mechanism and the recliner mechanism, characterized in that the seat frame is further movable to an additional forward position in which the seat frame is further forward than in the fully up position.

2. The seat frame of claim 1, wherein in the additional forward position the seat frame is 70-100mm more forward than in the fully upward position.

3. The seat frame according to claim 1 or 2, characterized in that the seat frame further comprises a reclining mechanism that adjusts a reclining angle of the seat frame.

4. A seat frame as claimed in claim 3, wherein the recliner mechanism includes a recliner link having the other end pivotally connected to one end of the recliner link and the other end pivotally connected to a front bracket at the upper portion of the base; and a tilt drive mechanism that drives the tilt adjustment link in rotation about its pivot point with the base.

5. The seat frame according to claim 4, wherein the reclining drive mechanism includes a spindle motor that is arranged in a direction perpendicular to the seat front-rear direction; and a screw engaged with an output end of the spindle motor, wherein the spindle motor is disposed on the tilt adjusting link, one end of the screw is disposed on a front side bracket at an upper portion of the base, and wherein rotation of the output end of the spindle motor causes the spindle motor to move along the screw, driving the tilt adjusting link to rotate about a pivot point thereof with the base.

6. A seat frame as claimed in claim 3, wherein the reclining mechanism includes a spindle motor disposed along the seat front-rear direction; and a screw engaged with an output end of the spindle motor, wherein the spindle motor is disposed on a front side of a rim of the seat frame, and one end of the screw is disposed on a front side bracket at an upper portion of the base, wherein rotation of the output end of the spindle motor causes it to move along the screw, whereby the spindle motor and the screw constitute a front link of adjustable length, wherein a length of the front link is adjusted by a stroke length of the spindle motor along the screw.

7. A seat frame as claimed in claim 1 or claim 2, wherein the other end of the front link is pivotally connected to a front side bracket at the upper part of the base, and wherein the seat frame is reclined back and down by the height adjustment mechanism so that the height adjustment mechanism also functions as a recliner mechanism.

8. The seat frame of claim 7, wherein the seat frame includes a seat pan on a front side that is tiltable upwardly relative to a rim of the seat frame.

9. The seat frame of claim 7, wherein the seat frame does not include any recliner mechanism on the front side.

10. The seat frame according to claim 7, wherein the height adjusting mechanism includes a spindle motor arranged in a seat front-rear direction; and a screw engaged with an output end of the spindle motor, wherein the spindle motor is disposed on the rear link, and one end of the screw is disposed on a rear bracket at an upper portion of the base, such that rotation of the output end of the spindle motor causes movement thereof along the screw, driving the rear link to rotate about its pivot point with the base.

11. The seat frame according to claim 7, wherein the height adjusting mechanism includes a height driving motor that is arranged in the seat front-rear direction; the driving gear is in transmission connection with the output shaft of the motor; and a rack engaged therewith, wherein the rack is provided on the rear link, and the motor and the drive gear are provided on the rear side of the bezel of the seat frame.

12. The seat frame of claim 4, further comprising a front synchronizing bar, wherein both ends of the front synchronizing bar are fixedly connected to pivot connection points of the base and the reclining link at left and right sides of the seat frame, respectively.

13. A seat frame as claimed in claim 1 or claim 2, wherein the base is of a track construction, the seat frame being capable of sliding along the track with the height adjustment mechanism by means of a front-rear drive mechanism.

14. A vehicle seat, characterized in that it comprises a seat frame according to any one of claims 1-13.

15. The vehicle seat of claim 14, wherein the vehicle seat is a zero gravity vehicle seat.