FR2568457A1 - DEVICE FOR ADJUSTING THE HEIGHT OF A BACKREST, IN PARTICULAR OFFICE SEAT. - Google Patents

Abstract

THE SUBJECT OF THE PRESENT INVENTION IS A DEVICE FOR ADJUSTING THE HEIGHT OF A BACKREST, IN PARTICULAR OF THE OFFICE SEAT. ACCORDING TO THE INVENTION, THE BODY3 HIDDEN IN ITS CENTRAL PART4 OF THE SAID ADJUSTING DEVICE1 IS PROVIDED WITH AT LEAST ONE LATERAL RECESSED7 HOUSED IN AT LEAST ONE OF ITS VERTICAL WALLS6 AND INTENDED TO LODGE A TIGHTENING MEANS WHEN THIS IS IN ITS POSITION OF UNLOCKING, WHICH LATERAL RECESS 7 IS TANGENT TO THE CENTRAL RECESS 4 SO AS TO COMMUNICATE WITH THE LATTER AND TO ALLOW FORCE TIGHTENING OF THE SAID DEVICE1 AGAINST A FACE21 OF A GUIDING AND SUPPORT TUBE5, SOLID WITH THE SEAT, WHEN TIGHTENING IS IN ITS BLOCKED POSITION, THE PASSAGE FROM ONE PORTION TO THE OTHER TAKING PLACE BY TILTING. APPLICATION TO THE CONSTRUCTION OF SEATS, IN PARTICULAR OFFICE.

Description

The present invention relates to a device for adjusting the

  height of a folder, including office chair. Apart from the height adjustment devices of the backrest of a seat of the type comprising more or less sophisticated mechanisms - including gear systems - which are outside the scope of the present invention, there are different adjustment devices, simpler design, allowing sliding adjustment and

  tightening by screwing a backrest with respect to a vertical rod

  tical (or to a vertical tube) protruding from the rear central part of the seat to which this rod (or this

  tube) is connected by any appropriate means.

  A first type of backrest comprises a metal part, in particular chrome, folded substantially L-shaped, pierced at the central part and provided with two lateral wings, also pierced at their central part, which make

  protruding from the transverse sides of the E.parallel-

  the central side of the latter: this piece is fixed to the back of the backrest by means of two rubber studs (in each of which is embedded a metal reinforcement insert) providing a deformable connection between the piece and the backrest and so a flexibility of

movement to the user.

  In the space delimited by cooperation between the rear face of the backrest, said C-piece and said two studs, is inserted said vertical rod projecting from the rear central part of the seat, which is applied against the central side of the piece. C and which is provided, in the second upper half, with an axial window

  oblong along which can slide the

of said room.

  A screw is inserted into the aforesaid space to make it pass through said oblong window and said central bore of the C-piece, so as to be applied by its head against the rod and to allow the fixing, at the desired height, of the folder by sliding the latter along

  this rod and by tightening with a specially shaped nut

  ciale, allowing easy handling, which is screwed around said screw. In a second type a tube, in particular consisting of a flat with round edges, also protruding from the rear central part of the seat, is surrounded by a substantially parallelepipedal part and provided over its entire height with a central recess allowing its sliding on along this tube. This piece is secured to the back surface of the backrest by a first piece E which

  cooperates with a second piece C_, whose transverse sides

  versaux du - are articulated with the corresponding sides of said first piece in [, to ensure the necessary flexibility of movement to the user: a screw provided with a head facilitating its handling through a tapped hole in the central side of the second E-piece and the opposite wall of said parallelepiped part, so as to reach the wall of said tube and to ensure by tightening by screwing maintaining the backrest in the desired position. However, the height adjustment devices of a folder of the prior art have a number of disadvantages, including:

  - with regard to tightening by screwing, the application re-

  of the latter damages the state of the rear surface portion of the tube, along which the various positioning movements of the backrest are made and which is apparent to be opposed to the front surface of the tube which is hidden by the backrest. which gives an aesthetically unpleasant aspect to the file,

  - as regards the means of support for the file, that

  it needs to be machined, which affects the manufacturing price of the seat,

  - with regard to the price of parts ensuring by cooperation

  the height adjustment of the backrest, it is sensitive-

high,

  - with regard to clamping operations by means of

  wise, sliding and screwing, these are relatively long and tedious, - as regards the structure, it has protruding parts, including nuts or clamping screws, which entail the risk of tearing

accidental clothing.

  The present invention therefore aims to provide a file of the type comprising a height adjustment device that better meets the needs of practice that records aimed at the same purpose previously

known.

  The present invention relates to a device for adjusting the height of an office seat back, by means of a clamping means against a guide and support means, in particular constituted by a tube, preferably a flat tube with round edges, which projects upwardly from the rear central part of the seat, which

  adjusting device is of the type comprising a sensing body

  parallelepipedally fixed which is fixed to the rear face of the backrest by a suitable fastening means and which is provided over its entire height with a central recess allowing the sliding of this body and thus the backrest which it is integral with respect to said guide tube and support, which adjusting device is characterized in that the body recessed at its central portion is provided with at least one lateral recess formed in at least one of its vertical walls and for accommodating said clamping means when it is in its unlocking position, and in that this lateral recess is tangent to said central recess so as to communicate with the latter and to allow the said device to be clamped against a face of the said guide and support tube when the said clamping means is in its blocking position, the passage from this position to said unlocking position taking place by a tilting operation of said locking means using a suitable means of maneuver. According to a preferred embodiment of the device according to the invention, said clamping means is constituted by a rod having substantially at its median portion a projecting portion, in particular obtained by soyage, which rod is intended to be housed in said tangent lateral recess central recess, so that its projecting portion protrudes from the medial portion of the lateral recess, when the rod is in the locking position, to tighten the height adjustment device of the backrest against a

  face of said guide tube and support.

  According to another preferred embodiment of the device according to the invention, said lateral recess is horizontal and is formed in the vertical wall of said hollow body which is on the side of the rear face of the backrest, namely which is applied against the face before said guide tube and support which is hidden by the folder.

  According to an advantageous variant of this embodiment of

  tion, said lateral recess is vertical and is arranged

  in any of the vertical walls of said hollow body.

  According to another advantageous variant of this embodiment, said lateral recess is oblique and in particular oriented along the diagonal of any one

walls of said hollow body.

  According to another advantageous embodiment of the device according to the invention, said means for operating the clamping rod is constituted by a handle provided with a recess for accommodating a portion of this rod bent at 90 relative to said portion. which is housed in said lateral recess in the recessed body at its

central part.

  According to an advantageous arrangement of this embodiment, said handle has in cross section

  substantially an L shape and is provided at its upper portion

  upper portion of a connecting portion between the two sides of the L, one side is a gripping wing, and in which is formed said recess for housing the bent portion

outer of the clamping rod.

  According to yet another advantageous embodiment

  the device according to the invention, said means for attaching the body to the back of the backrest is constituted by a base made by molding in one piece with this body and having two lateral lugs fastening by screwing. According to an advantageous arrangement of this embodiment, the attachment lug which is on the side of said operating handle has, on its upper edge and on the side of said hollow body, a recess which is intended to house the upper part of the handle. when it is in the unlocking position and whose vertical face abuts for the upper part of this handle, so as to limit substantially to 90 its tilting from the

blocking position.

  According to another advantageous arrangement of this embodiment, said base has on the face which is applied against the back of the lightening recesses, one of which communicates in particular with said lateral recesses.

and central.

  According to an advantageous embodiment of the arrangement

  in accordance with the invention, it cooperates with a means

  stopper constituted by a piece that caps the end of the

  upper mity of said guide tube and support.

  According to an advantageous arrangement of this embodiment, said abutment piece has on its inner walls lugs protruding from these walls and ensuring the holding in position of this part after being force-applied on said upper end of the tube.

guidance and support.

  In addition to the foregoing, the invention also includes other arrangements which will be apparent from

the following description.

  The invention will be better understood by means of the

  description which will follow, which refers to the drawings

  attached in which: - Figure 1 shows a front view of the device according to the invention for adjusting the height of a folder, including office chair, which is secured to the folder and shown in its locking position, - the FIG. 2 shows a side view of the assembly represented in FIG. 1, with the device according to the invention in its unlocking position; FIGS. 3a, 3b, 3c represent front views,

  above and in section along III, respectively, of the

  for adjusting the height of a backrest seat according to the invention, FIG. 4 shows a view from above of the clamping means according to the invention intended to cooperate with the device represented in FIGS. 1, 2, 3a, 3b, 3c and provided with its

  operating means according to the invention.

  FIGS. 5a, 5b, 5c show side, front and still side views, respectively, of the operating means illustrated in FIG. 4; FIG. 6 shows a view from below of the stop means which

  cooperates with the device according to the invention and is

  also shown in Figures 1 and 2 according to

tale and side, respectively.

  It must be understood, however, that these

  and the corresponding descriptive parts, are given solely by way of illustration of the object of the invention,

  which they do not constitute in any way a limitation.

  The device for adjusting the height of the backrest 2 of a desk seat (not shown) comprises (see FIGS. 3a, 3b and 3c) a body 3 provided at its central part with a recess 4 allowing the sliding of this body 3, after being secured to said backrest 2, along a guide means and support of this assembly, which means is preferably constituted by a flat tube 5 with round edges which projects from the rear central part of said seat. In the vertical wall 6 of the body 3, which is on the side of the backrest 2, is formed over its entire width a lateral and horizontal recess 7 which is tangent relative to said central recess 4, so as to communicate with the latter to its part. median 7a and to cooperate with the means of

  tightening according to the invention which will be described later.

  The hollow body 3 is attached to the rear face 8 of the

  backrest 2 via a base 9 made by

  lage in one piece with the body 3 and integral with the wall 6, which base is provided with two lateral lugs 10a, 10b of fixing by screwing to the back 2: two screws 11 pass through two holes 12 each formed in one of said lugs 10a and 10b and are screwed into tapped holes in the rear face 8 of said backrest 2o Said lateral and horizontal recess 7 opens out through the orifice 13 (see Figure 3a) located on a connection 14 came from molding and connecting the ear

fastening 10a to the body 3.

  The attachment lug 10b has a recess at its upper edge and next to the body 3, which

  the function will be described later.

  FIGS. 3a-3b and 3c also show lightening recesses 16a, 16bD 16c and 16d, integrally molded, of which the recess 16d is in

  communication with said lateral 7 and central recesses 4.

  With regard to the blocking of the device 1, and therefore of the backrest 2 of which it is integral, at the desired height, according to the invention, a clamping means (see FIG. having two portions 18 and 19 arranged at right angles to each other. The first portion 18 is provided, substantially at its middle portion, with a projecting portion 20, in particular obtained by sinking, and is intended to be housed in said lateral and horizontal recess 7, so that said projecting portion 20 of the rod 17 protrudes from the corresponding median portion 7a of this recess 7 and clamps the device 1 against the front face 21 of said guide tube

and support 5.

  It should be noted here that the use of a flat tube (or in general of a tube of rectangular or square cross-section) makes it possible to carry out the clamping by means of a bearing surface (especially the along the protruding part 20) and not just one point, as this

would be the case with a round tube.

  It should also be noted that, since the face 21 of the tube 5 is hidden by the backrest 2, the possible deterioration of the state of this face within the sliding limits of the device 1, due to the tightening of the latter against the tube 5, is not apparent, which is advantageous

from the aesthetic point of view.

  The portion 19 of the rod 17, folded relative to said portion 18, is located outside said recess 7, on the side of the attachment lug 10b, and is forcibly housed in a recess 22 formed in a handle

  Operating D 23 (see also Figures 5a, 5b and 5c).

  More precisely, this handle 23 has a substantially L-shaped cross-section and is provided at its upper portion with a portion 24 connecting the two sides 25 and 26 of the L and in which

is recess 22.

  The unlocking of the device 1 is obtained by means of

  said handle 23 between its locking position, corresponding to Figures 1, 4 and 5a to 5c, and its unblocking position shown in phantom in Figure 2: the side 25 of the L is a gripping wing which facilitates the tilting operation of the handle 23, and at the end of this tilting, said portion 24 of the latter is housed in said recess 15 of the attachment lug

  1Ob, whose vertical face 27 abuts for the upper portion

  said handle 23, so as to limit the flip-flop

substantially 90.

  It may be noted that, on the one hand, the lower side of the gripping wing 25 is inclined to follow the profile of the lower side of the attachment lug 10b and that, on the other hand, also the upper part of said portion 24 is tilted to follow the profile of the upper side of this

same ear 10b.

  Moreover, we can appreciate the absence, in the

  positive adjustment according to the present invention, of parts

  which are always troublesome for the reasons expo-

above.

  The device for adjusting the height of the backrest

  2 according to the invention cooperates with a stop constituting

  killed by a piece 28 which caps the upper end of said guide tube 5 and support (see Figures 1, 2 and 6) and which is applied by force on this end through the

  presence of lugs 29 projecting from its inner surface.

  The device 1 and the operating handle 23 are made of plastics material, preferably

polypropylene.

  In addition, said connecting rod 17, which is

  It is advantageously protected against galvanic corrosion, in particular by means of a soft iron stretch of appropriate diameter. Regarding the flexibility of movement of the backrest 2, it is obtained in a manner known per se by giving the rear face 8 of the backrest 2 a conformation to

double curve.

  As is apparent from the foregoing, the invention

  tion is not limited to those of its modes of

  tion and application just described in a more explicit way; on the contrary, it embraces all the variants that may come to the mind of the technician in the field, without departing from the scope or scope of the

present invention.

Claims (12)

  1.- Device for adjusting the height of a backrest (2), in particular of the office chair, by means of a clamping means against a guiding and support means, in particular consisting of a tube, of preferably a flat tube with round edges (5), which protrudes upwards from the rear central part of the seat, which adjusting device is of the type comprising a substantially parallelepipedal body (3) which is fixed to the rear face ( 8) of the file (2) by an appropriate means of   provided all along its height with a central recess (4)   putting the sliding of this body (3), and thus of the backrest (2) with which it is integral, with respect to said guide and support tube (5), which adjusting device (1) is characterized in that the body ( 3) recessed at its central portion (4) is provided with at least one lateral recess (7) formed in at least one of its vertical walls (6) and intended to accommodate said clamping means when it is in its position of unblocking, and in that this lateral recess (7) is tangent to said central recess (4) so as to communicate   with the latter and to allow for the forced tightening of that   positive (1) against a face (21) of said guide tube and   support (5) when said clamping means is in its posi-   blocking, the transition from this position to that position   deblocking operation taking place by a tilting operation of said clamping means by means of a suitable operating means.   2. Device according to claim 1, characterized   characterized in that said clamping means is constituted by a rod (17) having substantially at its median portion a projecting portion (20), in particular obtained by sinking, which rod (17) is intended to be housed in said lateral recess (7). ) tangent to said central recess (4), so that its projecting portion (20) protrudes from the middle portion (7a) of the lateral recess (7), when the stem (17) is in the locking position, to tighten the device (1) for adjusting the height of the backrest (2) against a face (21) of said guide and support tube (5).   3. Device according to claim 1, characterized   in that said lateral recess (7) is horizontal and is formed in the vertical wall (6) of said recessed body (3) which is on the side of the rear face (8) of the backrest (2), namely which is applied against the front face (21) of said guide and support tube (5) which is hidden by the folder (2).   4.- Device according to claim 1, characterized   in that said lateral recess is vertical and is provided in any one of the vertical walls of said body hollow (3).   5. Device according to claim 1, characterized   in that said lateral recess is oblique and in particular oriented along the diagonal of any one of walls of said hollow body (3).   6. Device according to any one of the   1 to 3, characterized in that said means for actuating the clamping rod (17) is constituted by a handle (23) provided with a recess (22) intended to house a part (19) of this rod (17). ) folded at 90 relative to said portion (18) which is housed in said lateral recess (7) arranged   in the body (3) hollowed out at its central part (4).   7.- Device according to claim 6, characterized   in that said handle (23) has a transom section   substantially L-shaped and is provided at its upper portion with a portion (24) connecting the two sides (25, 26) of the L, one side of which constitutes a gripping wing (25), and wherein is provided said recess (22) for accommodating the outer bent portion (19) of the clamping rod (17).   8. Device according to claim 1, characterized   in that said means for fastening the body (3) to the rear face (8) of the backrest (2) is constituted by a base (9) molded in one piece with this body (3) and having two lateral lugs (10a, 10Ob) for fixing by screwing (11).   9. A device according to claim 8, characterized in that the attachment lug (10b) on the side of said operating handle (23) has, on its   upper edge and the side of said hollow body (3), a pick-up   (15) which is intended to house the upper part (24) of the handle (23), when the latter is in the unlocking position, and whose vertical face (27) abuts the upper part (24). of this handle (23) so as to limit substantially to 90 its tilting from the blocking position.   10.- Device according to claim 8, characterized   characterized in that said base (9) has on the face which is applied against the backrest (2) relief recesses (16a, 16b, 16c, 16d), a recess (16d) communicates in particular with said lateral recesses (7) and central (4).   11.- Device according to any one of the   cations 1 to 10, characterized in that it cooperates with a stop means constituted by a piece (28) which forcibly caps the upper end of said guide tube and support (5).   12. Device according to claim 11, characterized   risé in that said piece (28) abutment has on its inner walls lugs (29) projecting from these walls and ensuring the maintenance in position of this piece (28)   after having been force-applied on the said upper extremity   the guide and support tube (5).