A headrest for motor vehicle seats

Abstract: A headrest (19 for motor vehicle seats (S), wherein the support rods (8) are frictionally slidable through respective bushes (15) in turn engaged within respective tubular elements (16) adapted to be inserted in the seat back (S). Each support rod is provided inferiorly with a notch (14) defining a maximum-height position for the body (2) of the headrest (1), and each bush (15) carries a sliding pressure member (25) which is urged into slidable contact against the corresponding rod (8) under the action of a spring (26). The pressure member (25) is engageable in the notch (14) of the support rod (8) in the maximum-height position of the body (2), and can be disengaged by means of a control push button (27) positioned at the top of the seat back (S).

Description: The present invention is related to headrests for motor vehicle seats, of the type comprising a resilient body in which a load bearing frame is embodied, having two lateral hollow parts within which are placed two respective support rods adapted to be inserted inferiorly within corresponding housings provided in the top zone of a seat back, and wherein first adjusting means for varying the height position of the headrest and second adjusting means for modifying the orientation of the headrest relative to the seat back are provided. A headrest of the above-mentioned type is generally known, for instance, from EP-B-0 322 373 in the name of the same Applicant, according to which the height adjustment of the headrest is accomplished by means of a stepped system between the resilient body and the two support rods, and the orientation adjustment is carried out through two sections of the rods, mutually articulated to each other below the headrest body. More particularly, the invention is directed to a headrest according to the pre-chacacterising portion of claim 1, and generally known from FR-A-2 571 317. The main object of the present invention is to make the height adjustment of the headrest more simple and efficient, by means of a continuous variation, simplifying at the same time assembling of the headrest relative to the seat back. A further object of the invention is to provide a headrest of the above-mentioned type which, in the assembled condition on the vehicle seat back, is free from plays and vibrations, so as to ensure effective steadiness and better comfort for the user. Still another object of the invention is to provide a sturdy as well as easy and cheap to manufacture headrest, even in connection with adjustment of the orientation of the resilient body relative to the seat back. The above objects are achieved, according to the invention, by virtue of the combination of features set forth in the characterising portion of claim 1. The first feature of such claimed combination is generally known per se from FR-A-2 671 587. Additional features of the invention are set forth in sub-claims 2 through 6. The invention will now be described in details with reference to the accompanying drawings, provided only by way of non limiting example, in which: -Figure 1 is a front-elevation fragmentary and partially sectioned view showing a headrest according to the invention, -Figure 2 is a vertically-sectioned view taken along line II-II of Figure 1, - Figure 3 is a view analogous to Figure 2 in the maximum-height position of the headrest, - Figure 4 is a horizontally-sectioned partial view taken along line IV-IV of Figure 1, - Figure 5 is a view identical to Figure 4 in the maximum-height position of Figure 3, - Figure 6 is a view anologous to Figure 1 of a second embodiment of the invention, - Figure 7 is a vertically-sectioned view taken along line VII-VII of Figure 6, and - Figure 8 is a view analogous to Figure 7 in the maximum-height position of the headrest. Referring initially to the embodiment shown in Figures 1 through 5, reference numeral 1 generally designates a headrest according to the invention, applied on the top of the seat back S of a motor vehicle seat. In the following description and Claims the terms "upper", "lower" and the like are intended to be referred to the condition of use of the headrest such as shown in the drawings. The headrest 1 comprises, in a generally conventional way, a resilient body 2, normally made of foamed plastic material, provided with an outer covering 3 and containing a rigid load bearing frame 4 conveniently made of molded plastic material. The load bearing frame 4 is formed with two lateral hollow parts 5 having in the vertical plane of Figure 1 a constant width, and having in the vertical plane of Figures 3 and 4 a width progressively increasing downwardly, i.e. towards the base of the headrest indicated as 1a. In correspondence of said base 1a, a cover 6 is fixed to the load bearig frame 4 by means of a snap-fit engagement and, in case, auxiliary screws 7. The cover 6 has an aesthetical function, and also accomplishes the task of retaining the lower portion of the outer covering 3. Reference numerals 8 indicate two support rods, normally made of metal, by which the body 2 is supported on top of the seat back S, with adjustable height and orientation relative thereto, in the way explained herebelow. Each support rod 8 is monolithic and is provided in proximity of its upper end with a transverse hole 9 through which a pivot pin 10, carried by the load bearing frame 4 adjacent to the top of the respective hollow lateral part 5, is fitted. The rod 8 passes through a corresponding opening 11 of the cover 6 and protrudes below the body 2 with a lower one-piece part, having a substantially straight portion 12 and a final arcuate-shaped portion 13, both having a circular cross section and connected to each other through an annular groove 14. The portion 12 of each support rod 8 is frictionally slidably engaged through a respective bush 15, normally made of molded plastic material, which in turn is fitted within a respective tubular element 16, inserted from above into a housing A formed at the top of of the seat back S. As it can be better seen in Figures 4 and 5, each tubular element 16 has an enlarged cross section, and the corresponding bush 15 is formed with an outer axial centering rib 17 and, above the latter, with at least one locking tooth 18 which is axially and irreversibly snap-engaged within a corresponding axial slit 19 formed in the tubular element 16. The two tubular elements 16 associated with the two support rods 8 are rigidly connected to a transverse support body 20 which in turn is fixed to the structure of the seat back S within the housing A. This disposition ensures the correct mutual parallelism of the two tubular elements 16, as well as an even distribution of the loads applied, in use, to the headrest 1. Each bush 15 is further provided with an end portion 21 extending below the corresponding tubular element 16 and having a radially-contractable configuration originated by at least one axial slot 22 (Figure 1) and by the presence of a peripheral elastic ring 23 therearound. Such a configuration defines a first area of frictional sliding between the lower part 12, 13 of the rod 8 and the respective bush 15. Above the respective tubular element 16, each bush 15 is provided with an enlarged hollow head 24 placed outside the top of the seat back S and within which is movable a pressure member 25, urged in sliding contact against the portion 12 of the correspoding support rod 8, transverse thereto, by the thrust of a reaction helical spring 26. As it is better shown in Figures 4 and 5, the pressure member 25 is formed on the inner edge of an annular push button 27 pivotally mounted around a vertical pin 28 carried by the bush 15 and having a manoeuvre portion 27a protruding from an opening 29 of the enlarged head 24 and operable, against the action of the spring 26, to shift the pressure member 25 away from the portion 12 of the rod 8. The pressure member 25 and the spring 26 define a second area of frictional sliding between each support rod 8 and the corresponding bush 15. In use, the headrest 1 is movable between the fully lowered position depicted in Figures 1 and 2, and the fully raised position shown in Figure 3, and further, starting from such fully raised position, it can be removed from the seat back S. In the fully lowered position, the base 1a rests with a shape-matching upon the top of the seat back S. Starting from this position, a displacement of the body 2 upwardly performs the frictional sliding of the lower portions 12 and 13 of the support rods 8 relative to the bushes 15: as previously explained, friction is generated superiorly by the pressure members 25 and inferiorly by the elastically-contracted lower ends 21, with the addition of the arcuate shape of the terminal portions 13 of the rods 8 and of the resilient deformability of the bushes 15. The body 2 of the headrest 1 can then be positioned with a continuous adjustment at any intermediate height comprised between the fully lowered and fully raised positions, firmly maintaining the selected position. The fully raised position of Figure 3 is reached as soon as the peripheral grooves 14 are placed at the level of the enlarged heads 24 of the bushes 15: in such a position, the pressure members 25 are engaged within the respective grooves 14, under the action of springs 26. This situation is also depicted in the left side of Figure 5. A further displacement of the body 2 upwardly, so as to perform the complete extraction of the rods 8 from the bushes 15 and thus the removal of the headrest 1 from the seat back S, is only allowed following actuation of the push buttons 27, so as to withdraw the pressure members 25 from the grooves 14. The pivot pins 10 between the upper ends of the support rods 8 and the load bearing frame 4 allow adjustment of the angular position of the body 2 relative to the said rods 8 and, therefore, relative to the seat back S. The alternative embodiment shown in Figures 6 through 8 differs from the embodiment of Figures 1-5 solely as far as the system for adjusting the angular orientation of the headrest 1 is concerned. Therefore, only these differences will be described herebelow, using the same numeral references for parts which are identical or similar to those of the embodiment described in the foregoing. A hollow plastic-material element 29 is applied by molding on the upper end of each support rod 8 ; adhesion thereof on the rod 8 can be improved by means of one or more outer impressions 30 of the latter. Each hollow element 29 is provided with an upper solid appendage 31 formed at the top with a central axial slot 32 , across which the respective pivot pin 10 is inserted. A helical thrust spring 33, housed within the slot 32 and held therein by means of a radial locking pin 34, urges the pivot 10 downwardly, against the bottom of the slot 32. Inferiorly, each hollow element 29 is formed with a pair of opposed outer lateral teeth 35 (Figure 6) over which are engaged, under the action of the respective thrust spring 33, two toothed sectors 36 formed in the lower zones of the lateral sides of the corresponding tubular part 5 of the load bearing frame 4. In order to modify the angular position of the body 2 relative to the support rods 8, and thus relative to the seat back S, it is sufficient to displace upwardly the said body 2 so as to disengage the toothed sectors 36 from the lateral teeth 35, against the action of the springs 33. After reaching the desired position of adjustment, following release of the body 2 the headrest 1 is again firmly locked in the selected angular position. Evidently the utmost positions of angular adjustment are defined by the contrast , respectively frontal and dorsal, between the support rods 8 ( or their hollow elements 29 ) and the corresponding fore and back walls, respectively, of the relative lateral hollow parts 5 of the load bearing frame 4. It will be apparent from the foregoing that the headrest according to the invention is constituted by an essential number of components, adapted to be manufactured and assembled easily and economically. Mounting thereof on the seat back S can be performed with a high degree of accuracy and steadiness, and adjustment thereof in connection with both height and angular position can be carried out in a practical, convenient and functional way. Naturally the details of construction and the embodiments may be modified with respect to what has been described and illustrated, without departing from the scope of the present invention such as defined in the following claims.

Claims: A headrest (1) for motor vehicle seats (S), comprising a resilient body (2) in which a load bearing frame (4) is embodied, having two lateral hollow parts (5) within which are placed two respective support rods (8) adapted to be inserted inferiorly within corresponding housings (A) provided in the top zone of a seat back (S), wherein first adjusting means for varying the height position of the headrest (1) and second adjusting means for modifying the orientation of the headrest (1) relative to the seat back (S) are provided, and wherein the two support rods (8) are frictionally slidable through respective bushes (15) which in turn are fitted within respective tubular elements (16) adapted to be incorporated in the said housings (A) of the seat back (S), each of the said rods (8) having a notch (14) defining a maximum-height position of the headrest (1) and cooperating with stop means, characterised in that: the said stop means comprise a slidable pressure member (25) carried by each bush (15) above the respective tubular element (16) and urged into slidable contact against the corresponding support rod (8), substantially transverse thereto, by the action of a thrust spring (26), each said pressure member (25) being engageable in the notch (14) of the respective support rod (8) in the said maximum-height position of the headrest (1), and being associated with a control push button (27) operable to move the said pressure member (25) away from the support rod (8); the said two bushes (15) are resiliently deformable and are engaged within the respective tubular elements (16) by means of an irreversible axial snap coupling (18, 19); each bush (15) has a lower end portion (21) protruding from the corresponding tubular element (16) and resiliently tightened against the respective support rod (8). A headrest according to Claim 1, characterised in that the two tubular elements (16) are rigidly fixed to a transverse support body (20). A headrest according to Claim 1, characterised in that the support rods (8) have at least partially an arcuate configuration (13). A headrest according to any of the preceding Claims, characterised in that: the upper end of each support rod (8) is journalled to the load bearing frame (4) by means of a respective pivot pin (10), each of the the said tubular parts (5) of the load bearing frame (4) widens towards the base (1a) of the headrest (1), the upper end of each support rod (8) is provided with an axial slot (32) which is crossed by the said pivot pin (10) and in which an axial thrust spring (33), urging the said pivot pin (10) downwardly, is housed, each support rod (8) is provided with at least one lateral stop projection (35) on which is engaged, under the action of the respective thrust spring (33), at least one respective toothed sector (36) formed in the corresponding tubular part (5) of the load bearing frame (4). A headrest according to Claim 1, characterised in that the axial slot (32) with the thrust spring (33) and the said at least one stop projection (35) are formed on a hollow plastic-material element (29) molded over the upper end of the respective support rod (8). A headrest according to any of the preceding Claims, characterised in that the load bearing frame (4) is provided at the base (1a) of the headrest (1) with a snap- fitted cover (6).

Inventors: DE FILIPPO EMILIO, DE FILIPPO, EMILIO
Applicants: BRUZOLO MANIFATT GESTIND MB, GESTIND-M.B." MANIFATTURA DI BRUZOLO" S.P.A
Application year: 1992
Main classification: B60N2
IPC codes: B60N2