CN111391733A

CN111391733A - Electric headrest adjusting mechanism

Info

Publication number: CN111391733A
Application number: CN202010306018.XA
Authority: CN
Inventors: 张志会; 王奇; 陈景辉; 庄伟清; 常健
Original assignee: Yanfeng Adient Changshu Seating Mechanism Co Ltd
Current assignee: Keiper Changshu Seating Mechanisms Co Ltd
Priority date: 2020-04-17
Filing date: 2020-04-17
Publication date: 2020-07-10

Abstract

The invention relates to an electric headrest adjusting mechanism which comprises a driving assembly fixedly connected to a backrest, a support assembly fixedly connected to a headrest, and a screw rod with a longitudinal axis, wherein the screw rod is connected between the driving assembly and the support assembly to drive the support assembly to move along the longitudinal axis through the driving assembly, the support assembly comprises a cross beam fixedly connected to the headrest, the support assembly further comprises a first nut installed in the cross beam through a damping structure, and the screw rod and the first nut are matched to realize linear motion of the first nut along the longitudinal axis. According to the electric headrest adjusting mechanism, the screw rod is installed in a floating mode through the damping structure, so that the electric headrest adjusting mechanism can absorb shock and energy and can avoid the situation that the screw rod is clamped in stagnation in the prior art. Moreover, the electric headrest adjusting mechanism has the advantages of small number of parts and simple structure.

Description

Electric headrest adjusting mechanism

Technical Field

The present invention relates to automotive seats, and more particularly to an electric headrest adjusting mechanism.

Background

It is known to equip car seats with electrically adjustable headrests. Generally, a motor for driving a screw rod to rotate is fixed on the seat back, and a nut fixedly connected to the headrest is sleeved on the screw rod so as to drive the nut to move up and down on the screw rod through the motor to realize the up-and-down adjustment of the headrest. Practice shows that the phenomenon of lead screw clamping stagnation easily occurs in the existing corresponding adjusting mechanism.

Disclosure of Invention

The invention provides an electric headrest adjusting mechanism, aiming at solving the problem that a screw rod is blocked in the adjusting mechanism in the prior art.

The invention relates to an electric headrest adjusting mechanism which comprises a driving assembly fixedly connected to a backrest, a support assembly fixedly connected to a headrest and a screw rod with a longitudinal axis, wherein the screw rod is connected between the driving assembly and the support assembly to drive the support assembly to move along the longitudinal axis through the driving assembly, the support assembly comprises a cross beam fixedly connected to the headrest, the support assembly further comprises a first nut installed in the cross beam through a damping structure, and the screw rod and the first nut are matched to realize linear motion of the first nut along the longitudinal axis. It should be understood that the electric headrest adjusting mechanism of the present invention can absorb the installation error of the system through the floating connection between the damping structure and the cross beam, and can realize the vibration isolation and noise reduction functions through the damping structure.

Preferably, the cross beam has a frame-shaped space for accommodating the first nut and the damping structure, the damping structure includes two damping elements respectively disposed at opposite ends of the first nut, each damping element is a semi-closed structure, and the inner side of the damping element is contour-fitted with the first nut. It will be appreciated that each damping member receives and secures the first nut to prevent the damping structure from being removed from the first nut and to ensure that the first nut and the damping structure float together. In a preferred embodiment, an end surface of each damping element facing the first nut is formed with a sink into which opposite ends of the first nut are fitted. It should be understood that the frame-shaped space may be an oval, circular, rectangular, half-U-shaped, or other semi-enclosed space region.

Preferably, the end of the screw rod protrudes from the cross beam and is fixedly connected with a second nut for defining the low position of the headrest. In a preferred embodiment, the second nut is fixed to the screw by means of a fixed connection such as clinching.

Preferably, the drive assembly comprises a housing, a motor, a worm and a gear, wherein the housing is a hollow structure fixedly connected to the backrest, the motor, the worm and the gear are all accommodated in the housing, the motor is provided with a motor body and a rotatable drive shaft which laterally extends from the motor body along a transverse axis perpendicular to the longitudinal axis, the worm is fixedly connected to the drive shaft, the gear is meshed with the worm to form a meshing pair, and the screw rod extends into the housing and is fixedly connected with the gear.

Preferably, the housing is composed of a fixedly connected case and a case cover, and the motor body is mounted therebetween by form-fitting. It is understood that the motor is disposed in the closed space of the case and the case cover, which can improve the noise performance of the electric headrest adjusting mechanism of the present invention.

Preferably, the inner walls of the box body and the box cover are respectively provided with a thin rib plate which is slightly in interference fit with the external dimension of the motor body.

Preferably, one of the case body and the case cover has a guide groove and a catching hole, and the other of the case body and the case cover has a catch protruding to be caught in the catching hole along the guide groove.

Preferably, one of the case body and the case cover having the guide groove and the catching hole is formed as a double wall, and the catch on the other of the case body and the case cover is caught by being protruded into the double wall.

Preferably, the case body and/or the case cover has a U-shaped collar rib plate for supporting a collar of an end of the motor body, and a profile support rib plate for supporting the motor shaft.

Preferably, the inner wall of the box body is provided with a clamping groove, the flat gasket is perpendicular to the motor shaft and fixed in the clamping groove through two sides to be clamped in the clamping groove for installation, and the free end of the motor shaft is in contact with the flat gasket so as to support the motor shaft from the side. It will be appreciated that the side support structure reduces vibration and noise during motor operation and reduces noise during motor commutation.

According to the electric headrest adjusting mechanism, the screw rod is installed in a floating mode through the damping structure, so that the electric headrest adjusting mechanism can absorb shock and energy and can avoid the situation that the screw rod is clamped in stagnation in the prior art. Moreover, the electric headrest adjusting mechanism has the advantages of small number of parts and simple structure.

Drawings

Fig. 1 is a schematic structural view of a car seat including a power headrest adjusting mechanism according to a preferred embodiment of the present invention, which shows a process in which a headrest is moved from a high position to a middle position to a low position by means of the power headrest adjusting mechanism;

fig. 2 is an overall structural schematic view of the electric headrest adjusting mechanism of fig. 1;

FIG. 3 is an exploded view of FIG. 2;

FIG. 4A is a schematic structural view of the motor of FIG. 3;

FIG. 4B is a schematic structural view of the motor and case of FIG. 3;

FIG. 4C is a schematic structural view of the motor and cover of FIG. 3;

FIG. 5A shows the housing of FIG. 2;

FIG. 5B illustrates a housing of the motorized headrest adjustment mechanism according to another preferred embodiment of the present invention;

FIG. 5C illustrates a housing of the motorized headrest adjustment mechanism according to yet another preferred embodiment of the present invention;

FIG. 6 is a top view of the motor-mounted case of FIG. 2;

FIG. 7 is an enlarged fragmentary view of the motor-mounted case of FIG. 2;

fig. 8 is a schematic view of the motor-mounted case cover of fig. 2.

Detailed Description

The preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

As shown in fig. 1, a vehicle seat is mounted with a power headrest adjusting mechanism according to a preferred embodiment of the present invention, by which a headrest is sequentially moved from a high position to a middle position to a low position. The electric headrest adjusting mechanism comprises a driving assembly 1, a support assembly 2 and a screw rod 3, wherein the driving assembly 1 is fixedly connected to a backrest framework, the support assembly 2 is fixedly connected to a headrest guide rod, and the screw rod 3 with a longitudinal axis V is connected between the driving assembly 1 and the support assembly 2 so as to drive the support assembly 2 to move along the longitudinal axis V through the driving assembly 1, so that the headrest is driven to be adjusted.

As shown in fig. 2-3, the driving assembly 1 includes a housing 11, a motor 12, a worm 13 and a gear 14, wherein the housing 11 is a hollow structure fixedly connected (e.g., mounted by bolts) to the backrest frame (see fig. 1), and the motor 12, the worm 13 and the gear 14 are all accommodated in the housing 11. The motor 12 has a motor body 121 and a rotatable drive shaft 122 extending laterally from a central position of the motor body 121 along a transverse axis H perpendicular to the longitudinal axis V, the worm 13 is fixedly connected to the drive shaft 122 to be synchronously rotatable about the transverse axis H, the gear 14 is meshed with the worm 13 to form a meshing pair so as to drive the gear 14 to rotate about the longitudinal axis V by the motor 12, and the proximal end of the lead screw 3 extends into the housing 11 to be fixedly connected with the gear 14, so that the rotation of the lead screw 3 about the longitudinal axis V is finally realized. In this embodiment, the proximal end of the lead screw 3 is integrally molded in the gear to achieve synchronous motion. It will be appreciated that the proximal end of the lead screw 3 may also be fixedly connected to the gear 14 by splines/partial length teeth, or may be press-fitted into the gear 14 by interference. In addition, to reduce the coefficient of friction and improve system efficiency, drive shaft 122 is supported for rotation about transverse axis H within housing 11 by a first annular flat spacer, and gear 14 is supported for rotation about longitudinal axis V within housing 11 by a second annular flat spacer.

In the prior art, the motor is fixedly connected to the housing through the self-tapping screw to realize the half-pack type fixation, and the assembling relationship not only complicates the manufacturing process of the housing, but also is limited by the space requirement of the mounting screw and is generally only suitable for the motor with larger size. As shown in fig. 2 to 3, the housing 11 of the present invention is composed of a case 111 and a case cover 112 which are fixedly connected, and the motor body 121 is installed therebetween by shape-fitting, which not only avoids the use of self-tapping screws, optimizes the manufacturing process, has a simple structure and an attractive appearance, but also can assemble a motor having a small size accordingly, so that the total package of the electric headrest adjusting mechanism has a small size, and meets the diversified requirements of the frame connection. Specifically, the inner walls of the case 111 and the case cover 112 may respectively have a thin rib plate which slightly interferes with the outer dimensions of the motor body 121 to prevent the rotational movement of the motor body 121. As shown in fig. 4A-4C, the motor body 121 has a groove 1211, the box 111 has a rib 1111, and the box cover 112 has a rib 1121, the motor is axially positioned by the clearance fit of the

ribs

1111, 1121 and the groove 1211, so as to prevent the motor body 121 from axially moving during operation. In addition, the box 111 is also provided with a convex rib 1112, and the circumferential direction of the motor is positioned by the convex rib 1112 of the box and the circumferential outer shape clearance fit of the motor body 121, so that the circumferential direction movement of the motor body 121 is prevented during operation. In addition, two sets of windows are respectively arranged on the box body 111 and the box cover 112 to increase the heat dissipation performance when the motor operates.

In this embodiment, the box body 111 and the box cover 112 have a set of mounting holes for fixing the electric headrest adjusting mechanism of the present invention on the backrest frame (the mounting holes of the box body 111 and the box cover 112 can be combined and adjusted according to the mounting manner, and can be connected by a self-tapping screw or by a bolt, so as to facilitate mounting and adjustment); the box body 111 and the box cover 112 are also provided with a group of positioning shaft holes for realizing the positioning between the box body 111 and the box cover 112; the box 111 and the box cover 112 also have six sets of snap structures for coupling between the box 111 and the box cover 112. As shown in fig. 3 and 5A, a guide groove 111a and a fastening hole 111b are formed on a side wall of the box 111, and the box cover 112 has a fastening tab 112a extending therefrom to be fastened in the fastening hole 111b along the guide groove 111 a. In this embodiment, the inner side of the guide groove 111a is removed and thinned, and the outer side of the buckle 112a is removed and thinned, and this special cross-sectional structure not only makes the mold structure of the housing 11 simpler and easier to manufacture, but also facilitates demolding during manufacturing, and simultaneously ensures that the buckle 112a has sufficient flexibility and the stress concentration at the root of the buckle does not occur. It should be understood that the box body and the box cover can also have different buckling forms, for example, a guide groove and a buckling hole are formed on the side wall of the box cover, and the box body is provided with a protruding buckle to be buckled in the buckling hole along the guide groove; the box and the lid may be connected in other ways, for example, as shown in fig. 5B, the box 111 'and the lid 112' are connected by screws, and for example, as shown in fig. 5C, the box 111 "and the lid 112" are bonded by glue.

As shown in fig. 6, the side wall of the case 111 is formed as a double wall 111c in the snap area, so that the snap 112a (see fig. 3) protrudes into the double wall 111c inside the case 111. In this way, once the snap 112a is broken or damaged, its fragments are contained in the double wall 111c to avoid its entering into the worm-gear meshing pair to generate abnormal noise. In addition, the double-wall 111c can also have the function of an oil storage wall. That is, the double-wall 111c structure is a protection structure for ensuring that even if the buckle 112a is accidentally broken during assembly or operation, the buckle will not enter the gear engagement area, so that the adjusting mechanism of the electric headrest of the present invention generates sharp noise and even causes serious installation accidents. The structure plays a role in functional isolation, and is used for physically isolating the fixed features of the box body 111 and the box cover 112 from the transmission function of the gear box, so that the operation of the electric headrest adjusting mechanism is guaranteed.

As shown in fig. 7, the case 111 has a U-shaped collar rib 111d at the middle thereof for supporting the collar 121a of the end of the motor body 121. Specifically, the end of the case 111 has a contoured support rib 111e for supporting the motor shaft 122, which cooperates with the case cover 112 to prevent radial play. The inner wall of the box body 111 is provided with a clamping groove 111f, the flat gasket 15 is perpendicular to the motor shaft 122 and is clamped in the clamping groove 111f for installation, the free end of the motor shaft 122 is contacted with the center of the gasket 15 so as to support the motor shaft 122 from the side surface, axial clearance is eliminated, noise is eliminated, and sound quality is improved.

As shown in fig. 8, the case cover 112 has a U-shaped collar rib 112b at the middle thereof for supporting the collar 121a of the end of the motor body 121. The end of the cover 112 has a contoured support rib 112c for supporting the motor shaft 122 and cooperating with the housing 111 to prevent radial play. Referring to fig. 3, the cover 112 further has a pre-positioning hole structure 112d, and correspondingly, the backrest frame has a pre-positioning structure, and the pre-positioning structure on the backrest frame is inserted into the pre-positioning hole structure 112d of the cover 112 before the housing 11 is fixed to the backrest frame, so as to pre-position the housing 11. It should be understood that the housing 111 also has pre-positioning hole features that allow for reverse installation.

Returning to fig. 2 and 3, the bracket assembly 2 includes a cross member 21, a first nut 22 and a damping structure 23, wherein both ends of the cross member 21 are fixedly connected to the headrest guide rods (e.g., through the opening holes 21a), and the first nut 22 is installed in the cross member 21 through the damping structure 23. In the present embodiment, the cross member 21 has a frame-shaped space 21b for accommodating the first nut 22 and the damping structure 23, and the damping structure 23 includes two damping elements (e.g., rubber pads) respectively provided at opposite ends of the first nut 22, and an end surface of each damping element facing the first nut 22 is formed with a sinking groove 23a so that the opposite ends of the first nut 22 sink into the sinking grooves 23 a. The distal end of the screw 3 extends from the cross member 21 through the cross member 21 and the damping structure 23 in threaded engagement with the first nut 22, and the distal end of the extension is fixedly connected with a second nut 31, so that the low position of the headrest is defined by means of the second nut 31, as shown in fig. 1. In this embodiment, the outer ring of the second nut 31 is fixedly attached to the distal end of the lead screw 3 by caulking to deform the inner hole. Thus, by means of the damping structure 23, the screw rod 3 is installed in a floating mode, and the damping structure can absorb shock and energy and can avoid the situation of screw rod clamping stagnation in the prior art.

The above embodiments are merely preferred embodiments of the present invention, which are not intended to limit the scope of the present invention, and various changes may be made in the above embodiments of the present invention. All simple and equivalent changes and modifications made according to the claims and the content of the specification of the present application fall within the scope of the claims of the present patent application. The invention has not been described in detail in order to avoid obscuring the invention.

Claims

1. The utility model provides an electronic headrest adjustment mechanism, its includes the drive assembly of fixed connection on the back, the support assembly of fixed connection on the headrest and has the lead screw of axis of ordinates, the lead screw is connected between drive assembly and support assembly in order to drive the support assembly through the drive assembly and remove along the axis of ordinates, the support assembly includes the crossbeam of fixed connection on the headrest, a serial communication port, the support assembly still includes installs the first nut in the crossbeam through damping structure, the linear motion of first nut along the axis of ordinates is realized in lead screw and the cooperation of first nut.

2. The motorized headrest adjusting mechanism according to claim 1, wherein the cross member has a frame-shaped space for receiving the first nut and the damping structure, the damping structure including two damping elements disposed at opposite ends of the first nut, respectively, each of the damping elements being a semi-closed structure, an inner side of the damping element being in contour fit with the first nut.

3. The electric headrest adjusting mechanism according to claim 1, wherein a distal end of the lead screw protrudes from the cross member and is fixedly connected with a second nut for defining a low position of the headrest.

4. The motorized headrest adjusting mechanism of claim 1, wherein the drive assembly includes a housing, a motor, a worm, and a gear, wherein the housing is a hollow structure fixedly attached to the backrest, the motor, the worm, and the gear are received in the housing, the motor has a motor body and a rotatable drive shaft extending laterally from the motor body along a transverse axis perpendicular to the longitudinal axis, the worm is fixedly attached to the drive shaft, the gear is engaged with the worm to form a pair of teeth, and the lead screw extends into the housing and is fixedly attached to the gear.

5. The electric headrest adjusting mechanism according to claim 4, wherein the housing is composed of a case and a cover fixedly connected, and the motor body is fitted therebetween by a form fit.

6. The electric headrest adjusting mechanism according to claim 5, wherein the inner walls of the box body and the box cover are respectively provided with a thin rib plate which is slightly in interference fit with the external dimension of the motor body.

7. The electric headrest adjusting mechanism according to claim 5, wherein one of the case body and the case cover has a guide groove and a catch hole, and the other of the case body and the case cover has a catch projecting to be caught in the catch hole along the guide groove.

8. The electric headrest adjusting mechanism according to claim 7, wherein one of the case and the cover having the guide groove and the catch hole is formed in a double wall, and the catch on the other of the case and the cover is inserted into the double wall and caught.

9. The electric headrest adjusting mechanism according to claim 5, wherein the box body and/or the box cover has a U-shaped collar rib plate for supporting a collar of an end portion of the motor body, and a profile support rib plate for supporting the motor shaft.

10. The electric headrest adjusting mechanism according to claim 5, wherein the inner wall of the housing is provided with a catching groove, a flat gasket is installed perpendicular to the motor shaft and caught in the catching groove by being fixed at both sides, and a free end of the motor shaft is in contact with the flat gasket to support the motor shaft from the side.