WO1989009557A1

WO1989009557A1 - An adjustable lumbar cushion used for chairs, arm-chairs and others

Info

Publication number: WO1989009557A1
Application number: PCT/IT1989/000023
Authority: WO
Inventors: Giordano Pasutto; Antonio Guglielmo Lucia
Original assignee: Giordano Pasutto; Antonio Guglielmo Lucia
Priority date: 1988-04-12
Filing date: 1989-04-10
Publication date: 1989-10-19
Also published as: IT8847837A0; IT1219524B; AU3423589A

Abstract

A lumbar cushion for seats, chairs and the like, comprising a horizontal elongated body (15; 115; 215; 315) which is shaped with a front convexity to match the body surface of a person having a proper lordosis at lumbar vertebrae; said body being either independent of or integral with a chair-back. Such a cushion, connected to arms determining its correct position, is sustained by a support element (10; 102; 202; 353) of chair-back or the like and it is height adjustable with respect to the latter by adjusting means with tightening screws (21a, 21b, 27; 121a, 121b, 127) or with gears (221a, 233-237; 337, 343-351; 343', 354-357), or springs, cylinders, etc. which can be either manually or automatically controlled.

Description

An adjustable lumbar cushion used for chairs, arm-chairs, and others.

The invention relates to an element which can either be added to or be an integral part of a structure of a chair, arm-chair or other furniture having a seat and a back, and more particularly it concerns an adjustable lumbar cushion suitable to insure that one can remain with one's own natural lordosis, i.e. that the human spine is curved with a forward convexity at the lumbar vertebrae.

In a child of school age scoliosis and spine's arthritis pratically do not exist. They are very rare in those adults, who have maintained the lumbar plexure in a natural convexity (lordosis) as children. The lordosis is important because it insures the erect posture of the person, as it provides the ideal static and dynamic basis to support all the remaining parts of the spine and the weight of the human body in the proper physiological position.

Therefore, the best prevention of the structural alterations of the spine, m its several segments, which can cause some deseases, such as arthritis, scoliosis, hernia of the spinal disks, sciatica, lumbagos and o^'therε, is to maintain the lordosis. The lordosis is lost primarily due to an incorrect seated position.

With the above mentioned purpose this invention provides for a lumbar cushion or support, comprised of a shaped body, whose shape is such that it matches the body's concavity at the level of the lumbar vertebrae, i.e. said shaped body having a proper length is frontally formed in a complementary manner to said portion of spine. Said shaped body, which is either constructed of or lined with a padding, can be provided either as an independent part separated from the chair's other back elements or an integral part of said back. In both cases the lumbar cushion is supported by the backrest, i.e. the support element of the back of any chair, seat or arm-chair in which it is provided, and can be height adjusted by locking it at the desired position by suitable support and adjusting means. Said heigth is determined by the level of the person's elbows, when his arms are close to his body in a rest position, with his forearms at right angle. It is not necessary to make reference to known types of chairs, seat or arm-chairs to which the lumbar cushion according to the invention is applicable. The hereinafter described embodiments of the invention will illustrate how the adjustable lumbar cushion can be adapted to small desk chairs of various design, school desks, arm-chairs, deck- chairs and seats used for means of transportation, in order to demonstrate its possibilities of application^* in a non restrictive manner. In order to improve the effectiveness of the cushion, it is preferable that the seat of the chair or the like is height adjustable, and that said adjustment is carried out when one is sitting with his feet flat on the floor with legs at a right angle to his thighs, and further that the same seat is slightly inclined rearwards to favour the rest of the human body against the chair-back.

As above mentioned and hereinafter shown in various embodiments, the adjustable lumbar cushion according to the invention, can be added to any chair or arm-chair of known type, at right angle to the element sustaining the chair-back, separately from the other parts of the same chair-back. Alternatively the adjustable lumbar cushion can be permanently fitted into a back, which is consequently modified, of a chair or arm-chair where conventional and/or improved seat adjusting means are provided. In the case of the lumbar cushion fitted into the chair-back, it can be made integral with the chair- back and hence the adjustment of the cushion simply involves the adjustment of the chair-back as a whole. Alternatively, the lumbar cushion can be made to slide up and down in a determined amount inside the chair-back, the ends of the cushion travelling parallel to each other inside of the chair-back.

In every embodiment where the lumbar cushion is used, there exists a constant positional relationship betw.een the lumbar cushion and the supporting means of the arms of the chair. Said relationship is generally fixed, as the bottom of the lumbar cushion is connected to the supporting means of the arms of the chair. However, a certain adjustment between cushion and arms of the chair could be provided in the horizontal position (depth) of the chair.

The lumbar cushion is attached to the arms of the chair, said arms having the desired length, as it has been empirically found that the central portion of the lumbar plexure is situated at the same height of the elbows of a person, when a person places his elbows close to his body in a resting position with his forearms bent at about 90° to be supported by the arms of the chair. According to these parameters, it is sufficient to create a relationship between the height of the arms of the chair and the height of the shaped body and/or the chair-back, making a single unit which can be moved along the height of the chair.

Therefore, in order to determine the correct position of the lumbar cushion and adapt it to the physique of a person, it is sufficient that the person sit down adjusting the lumbar cushion until he is comfortably resting his forearms on the arms of the chair. In some embodiments, the adjustment operation can be easily carried out by the same person who is seated: in other embodiments an external intervention is required. The lumbar cushion will be locked when it is in the correct position. At that time, the independent shaped body and/or the chair-back, which includes a shaped body of lumbar cushion, will be automatically positioned to support the human back by matching the cushion with the spine, helping the spine to keep its lordosis.

These and other features of the lumbar cushion or support of the invention will be more apparent by the following description of four embodiments including some different applications of the invention, with reference to the accompanying drawings, in which:

Figure 1 is a schematic side view of a chair, which is provided with the lumbar cushion of the invention carried out in accordance with its first embodiment;

Figure 2 is a rear view of the chair in Figure 1 ;

Figure 3 is an enlarged detail of the vertical section through line A-A in Figure 2: Figure 4 is an enlarged detail of the cross section through line B-B in Figure 3:

Figure 5 is a schematic side view of a chair, which is provided with the lumbar cushion of the invention in accordance with its second embodiment; Figure 6 is a rear view of the chair in Figure 5:

Figure 7 is an enlarged detail of the vertical section through line C-C in Figure 6;

Figure 8 is an enlarged detail of the section through line

D-D in Figure 7 • Figure 9 is a schematic side view of a chair, having a structural difference from that one of the precedent

Figures, which is provided with a lumbar cushion according to a third embodiment of the invention; Figure 10 is a rear view of the chair in Figure 9; Figure 11 is an enlarged detail of the vertical section through line E-E in Figure 10;

Figure 12 is an enlarged detail of the cross section through line F-F in Figure 11;

Figure 13 is a schematic side view of a row of school benches, each seat of which is provided with a lumbar cushion according to the third embodiment of the invention in different application; Figure 14 is a front view of the row of school benches in Figure 13;

Figures 15 and 16 are similar to Figures 13 and 14, but they indicate a double row of school benches; Figure 17 is a fragmentary vertical section of the seat of the school benches in Figureε 13 to 16;

Figure 18 is an axonometric view, with some parts thrown away, of a front seat of a car or other means of transportation, which is provided with the lumbar cushion according to a fourth embodiment of the invention; Figure 19 is an axonometric view of the lumbar cushion embodied in the seat in Figure 18, said cushion being provided with different adjusting means; Figure 20 and 21 are schematic side view of an airplane seat, which is provided with the lumbar cushion of the fourth embodiment of the invention, said seat having height adjusting means for the seat of the chair: Figure 22 is a schematic axonometric view of the height adjusting means for the seat of the chair in Figures 20 and 21 ;

Figure 23 is an axonometric view of a chair which is provided with the lumbar cushion and the seat according to the fourth embodiment of the invention: Figure 24 is an axonometric view of a small arm-chair which is provided with the lumbar cushion according to the fourth embodiment; and

Figure 25 is a schematic side view of a deck-chair or sofa-bed, which is provided with a lumbar cushion of the fourth embodiment of the invention according to a different application thereof.

Referring to Figures 1 a 4, an embodiment of the adjustable lumbar cushion of the invention has been shown as applied to a chair of a per se known design. In such a chair a base 1, is essentially a vertical tubolar element 2 which is provided with radial legs 3, each leg 3 having a caster 4 at its free end. Base 1 supports a mounting frame 8 for a shaped seat 9 in a height adjustable manner by means of a known kinematic chain wherein a screw 6 and a nut screw 7 (see Figures 1 and 2) are lockable and releasable by a lever 5. Mounting frame 8, which is generally horizontal, is an integral part of backrest indicated as a whole at 10, which supports a chair-b'ack 11. Chair-back 11 can be either secured or pivotally connected to backrest 10 at a X-X horizontal axis and locked to the same by screws 12 (as shown in Figure 1 ), in order to set thelβpe of the front rest surface 11a of chair-back 11, which normally adapts a shape matching the anatomical shape of the shoulders. Said chair-back 11 can also be made height adjustable in a per se known manner. In the chair shown in Figures 1 to 5, backrest 10 is in the form of a pair of tubolar parallel elements 10a,10b, which are fixed to frame 8 in the lower end thereof and are joined with each other in the upper ends 10c thereof. In the embodiment illustrated, chair-back 11 is attached in its rear part to a horizontal bar 13 (see Figure 1), which projects rearward with two orthogonal, vertical ears 13a. Ears 13a, having coaxial holes to X-X axis, are designed to be connected to corresponding ears of a bracket 14 in such a way that chair-back 11 can be tilted, before being locked to bracket 14 by screws 12. Bracket 14 is provided with known means (not shown) to slide along tubolar elements 10a,10b and to be locked at the desired height so that chair-back 11 is brought to the height of the shoulders of the person seated. According to this invention, said chair, which can also be of any similar design, must have the seat surface 9a sloping down and rearward, i.e. toward backrest 10, in such a manner to assist the man's body to rest against the chair-back 11, where an adjustable lumbar cushion according to this invention will be applied at backrest 10. The lumbar cushion according to a first embodiment (see Figure 3) of the invention, indicated generally as 16, is composed of a shaped body 15, having a frontal surface 15a formed with a convexity complementary to concavity or lordosis of spine at the lumbar vertebrae. Said shaped body 15,15a may include a padding and is fastened to a rear plate 17, which further supports, directly under shaped body 15, a holder. Said holder, which has a C-shaped form, is centrally connected to plate 17, from which two generally parallel arms 18a, 18a, holding the arms 19 of the chair, project forwards at the ends. In this embodiment, plate 17 is supported on tubolar elements 10a,10b of backrest 10 by a pair of shaped rods 21a, 21b and 22a, 22b, which are provided with facing slots 23a,23b and 24a, 24b, respectively, and are fastened together by screws 27, 28.

Said connection between lumbar cushion 16 and tubolar elements 10a, 10b allows said cushion to be adjusted at its height position, according to arms 19.

It will be sufficient that a person sit on seat 9,9a, screws 27 and 28 are released and said holder is either lowered or raised until it touches the elbows of the person. The person, keeping his arms close to the body and in rest position with his forearms at right angle, puts his forearms on arms 19 of the chair: now, said screws 27 and 28 are tightened. Shaped body 15 is automatically positioned exactly at the desired height to maintain lordosis. Referring now to Figures 5 to 8, therein is illustrated a second embodiment of the adjustable lumbar cushion in accordance with the invention as applied to a chair having a known design very similar to that one above described. Particularly, in Figures 5 and 6, the chair is made of a base 101, into which a mounting frame 108 for a shaped seat 109 is fitted. Also in this case frame 108 is connected to a backrest generally indicated as 110, which is in the form of a pair of tubolar parallel elements

110a,110b joining together in the upper end 110c thereof. In this second embodiment the lumbar cushion 116 is an integral part of the chair-back 111, being a forwardly convexed shaping of the lower portion of said chair-back. Lumbar cushion 116, as well as chair-back 111 as a whole, includes a shaped padding 115 with a frontal surface 115a and a rear support element 117 sustaining the padding 115. Rear support element 117 has two perpendicular, vertical ears 113a,113b, projecting rearwardly. Said ears 113a,113b, which are provided with coaxial holes of an X'-X' axis, are designed to be connected, by a pivot 112 provided with tightening means (not shown) , to corresponding holed ears 114 of a plate bracket 121a. This bracket 121a has a central body comprised of a flat plate, which is centrally bored at 125a and C-shape formed in its side vertical ends 122a, said C-shape having a curvature radius very near to the diameter of each of the two tubolar parallel elements 110a,110b of the backrest 110. Ears 114 are welded at right angle to the ends 122a of the bracket 121a. An' element 129 having a threaded hole and acting as a fixed nut for a locking screw 127, is also welded in the central portion of the bracket 121a on its face toward the chair- back 111 of the chair. Locking screw 127 is used to tighten in position a counter bracket 121b, which corresponds in a mirror-image relationship to bracket 121a. To this end, counter bracket 121b is also centrally bored at 125b to allow the locking screw 127 to be screwed. When the latter is tightened against the element 129, the side, vertical, curved ends 122a and 122b of the bracket 121a and the counter bracket 121b are connected by friction to the surface of tubolar parallel elements 110a and 110b, allowing the chair-back 111, and hence the lumbar cushion 116 as its integral part according to this second embodiment of the invention, to be height adjusted. The chair-back 111 may be tilted due to the pivot 112. In the chair above described armrest means are provided. Said armrest means is a support element similar to that one described with reference to the first embodiment, having a C-shaped form and comprising a horizontal central part 118 which is welded to the ear 114 and to element 129 of the bracket 121a. Two generally parallel arms 118a, supporting arms 119 of the chair, project forward from the ends of central part 118.

Also in the embodiment hereinabove described, the arms of the chair are integral with the lumbar cushion, which can be tilted independently of the constantly horizontal arms of the chair. Other ways of using the chair are the same to those described with reference to the first embodiment of the invention. The height and tilting adjustment of the lumbar cushion requires intervention of another person. To overcome this drawback, a third embodiment of the invention is provided as shown in its first application in Figures 9 to 12 (a rotating chair with casters) and in its second application in Figures 13 and 14 (school benches). Referring first to Figures 9 to 12, therein is illustrated a rotating chair with casters of a per se known design, in which a lumbar cushion according to this invention is embodied. Chair comprises a base 201 which is supported on casters 204 and a tubolar element 202. Tubolar element 202 is flexible and moveable in its lower part, but meanwhile it is rigid enough to sustain a chair-back 211 with arms, a seat 209 and, of course, the weight of a seated person. Chair-back 211, which- can be tilted in respect to an armholder 218, embodies the lumbar cushion 216 in accordance with the second embodiment. Chair-back 211 comprises a shaped padding 215 with a frontal surface 215a, which are the same to those above described, and a slightly modified rear support element 217 sustaining the padding. Said element 217 can be rotated around an X"-X" axis with respect to an armholder bracket 221a (see Figures 11 and 12) .

Armholder bracket 221a comprises a central sliding element 222a, which is designed to provide a prismatic coupling with a slide guide 230. Slide guide 230 is provided n the front of a rigid rearwardly sloping section 202a of tubolar support element 202. A rear part 231 of bracket 221a is fitted into a lenghtwise slot 232 of section 202a and comprises, as schematically shown in Figure 11, a nut screw portion 233, which is located between two side portions preventing rotation thereof. Sliding element 222a and nut screw portion 233 allow bracket 221a to travel along guide 230 when nut screw portion 233 is screwed on a threaded rod 234.

A bevel gear 235 is fixed to the lower end of threaded rod 234. Bevel gear 235 meshes (see Figure 12) with a bevel gear 236 which is fixed to the end of a pin which is an integral part of a handgrip 237. Handgrip 237 is located externally and laterally with respect to a rigid tubolar section 202a. The above described arrangement is such that one, sitting on the chair, may turn handgrip 237 and hence the connected bevel gear 236. Bevel gear 235, constantly in mesh with bevel gear 236 is also turned, as well as threaded rod 234, inside the nut screw portion 233 integral with bracket 221a, which is caused to be shifted with its slide portion 222a along guide 230. Chair back 211 and armholder 218, one being tiltable the other being fixed on bracket 221a, can be raised and lowered together according to the fisique of the person. A same adjusting device is provided for seat 209 of the chair, which is fastened to a support frame 208 slightly sloped rearwardly for reasons above explained. Such an adjusting device comprises a handgrip 237a, which is' located opposite with respect to handgrip 237 and is integral with a bevel gear 236a, and a bevel gear 235a, which is in mesh with the latter and is fixed to the end of a threaded rod 234a. Threaded rod 234a is enαaαed with nut screw portion 233a of slide bracket 208a of the support frame 208 of seat 209.

Figures 13 and 14 indicate a different application of a back with integral lumbar cushion and adjusting system of the same. A row of school benches is illustrated, each seat 238 being joine to the next writing-desk 239. The writing-desk is also height adjustable, depending on the level to which the elbows are brought when the person's arm is maintained close to the body and the forearm is kept at right angle said writing-desk being supported laterally by adjustable small legs 240 and being connected to the next unit by a central rigid frame 241. It should be apparent that the application of the cushion according to the invention is not limited to the specific structure of the frame and of the supports, and further changes are possibile, e.g. as that one of providing two or more school benches side by side in a row (see Figures 15 and 16). Handgrips 237' and 237a' which adjust the height of armholders 218^r of the back 211' with lumbar cushion 216' embodied, and of frame 208' of seat support 209' respectively, are shown in Figures 13 and 14. Both the seat supports 209' and the armholders 218' are turnable. The adjusting device having bevel gears (or spiral gears with orthogonal axes) (see Figure 17), which is similar to that described referring to Figures 11 and 12, is housed inside the supporting tubolar element 202'. It should be noted that the writing-desk also is height adjustable with a similar device, which is controlled by a handgrip 210' . The possible movements of the components of the school bench are clearly indicated by arrows in Figures 13 and 17. A fourth embodiment of the adjustable lumbar cushion according to the invention is shown in Figures 18 to 25. In this case, the lumbar cushion 316 is always permanently fixed into chair-back 311, while it is different in the various designs of seats and arm-chairs. It is always height adjustable with respect to the position of the arm and to the chair-back, which can be tilted in a conventional manner.

More specifically, Figure 18 illustrates the application of the lumbar cushion 316 according to the embodiment of a driver's car seat or other means of transportation. The lumbar cushion 316 generally comprises an elongated plano- convex body 315 made of padding having the desired stiffness, preferably soft foamed material. C-shaped support means is located lenghtwise inside said body 315, being projected from both sides of the latter, preventing it from rotation. Said C-shaped support means comprises a horizontal central part 318, which is almost completely contained inside the elongated body 316. Two generally parallel arms 318a, designed to support short revolving arms, project forward from the ends of central part 318. As schematically shown in Figure 18, the lumbar cushion, having a frontal surface 315a, is located inside of a conventional pad 342 of the seat with its convex, facing forward, portion creating a transversal swelling at the level of lumbar vertebrae of sitting person in chair-back 311. Cushion 316 is constrained in such a manner that it can slide in the direction of height along the back of the chair (up and down), keeping the cushion in a horizontal position. The cushion is moved by means of an adjusting device with bevel gears, according to the arrangement above illustrated. Such an arrangement comprises a rod 343 which is positioned horizontally and parallel to the cushion 316 inside of the padding. Said rod 343 has a handgrip 337 on its end which protrudes laterally from the padding 342 of the seat in an easily accessible position for a seated person. Two bevel gears 344,345 are fixed to rod 343 inside the padding. Bevel gears 344 and 345 mesh with bevel gears 346, and respectively 34.7, which are fixed to the end of rods 348 and 349. Each rod 348,349 is at a right angle to rod 343 and is screwed to a nut screw portion 350,351, which is an integral part of armholder 318 determining the height of the cushion 316. When handgrip 337 is turned either in one direction or in the opposite direction, the plano-convex body of cushion 316 is either raised or lowered until it reaches the required position inside the padding 432 (the movement of cushion is guided by armholder 318 sliding in the lateral slots 352 of the back frame 353). A modification of the adjusting device of the lumbar^* cushion 316 is shown in Figure 19. Spur gears 354, 355 are fixed to a control rod 343 ^r. Each spur gear 354,355 meshes respectively with a rack 356,357, which is integral with an armholder 318' . An application of the lumbar cushion 316 to an airplane seat is shown in Figures 2G and 21. Seat surface of such a seat is adjustable by a manual device with bevel gears as shown in Figure 22. This adjusting device, as well as those above described, can be substituted by springs, cylinders, etc. and assisted by electrical or hydraulic servomechanisms.

Other three applications of the lumbar cushion and adjusting devices thereof are illustrated in Figures 23 to 25, with reference to a chair with extensible legs, a chair on casters and a sofa-bed respectively. The illustrated applications, while not exhausting the argument, demonstrate the invention, which can be realized without changing or distorting its intentions and purposes.

Claims

Claims.

1. An adjustable lumbar cushion for seats, chairs, arm¬ chairs and similar furniture for homes, offices, schools, hospitals, public places and the like, ad for means of transportation, such as cars, trucks, pull ans, airplanes, the principal parts which constitute said articles, i.e. chair-seat, chair-back, arms, any head-rest and leg-rest, being normally provided with adjusting means thereof depending on the fisique of seated person, characterized in that it comprises: - a horizontally elongated body (15; 115; 215; 315), which is generally constructed from a padding with a front convexity such that its frontal surface (15a; 115a; 215a; 315a) can be superimposed at the lumbar vertebrae tc *-he body surface of a person who has a proper lordosis: - supporting means (17; 113a: 117: 217; 218) sustaining said elongated body, which is generally connected to arms (19; 119; 218; 218'; 318a) of the chair, to a backrest (10; 102; 202; 353) of the chair-back; and - adjusting means (21a,21b,27; 121a,121b,127 ; 221a,233- 237; 337,343-351; 343'; 354-357) which are connected to the unit constituted by said elongated body and by said support means thereof, and are acting on said backre-st of the back of the chair, said adjusting means being apt to adjust the relationship between lumbar cushion and chair- seat; the correct position of the lumbar cushion being determined by the position of the person's elbows and hence of the arms of the chair.

2. An adjustable lumbar cushion according to Claim 1, characterized in that said elongated body (15) of lumbar cushion is separated from back (11) of the chair.

3. An adjustable lumbar cushion according to Claim 1, characterized in that said elongated body (115, 215) is an integral part of the back element (111; 211). which together constitute the chair-back.

4. An adjustable lumbar cushion according to Claim 1, characterized in that said elongated body (315) is fitted inside the padding of the chair-back.

5. An adjustable lumbar cushion according to any Claims 1 to 3, characterized in that said adjusting means (21a,21b,27; 121a,121b,127) comprises at least one tightening screw and at least one pair of locking rods or plates by friction against at least one pair of tubolar elements (10a,10b; 10a',10b') of backrest (10).

6. An adjustable lumbar cushion according to any of Claims 1, 3 and 4, characterized in that said adjusting means

(221a,233-237; 337,343-351) comprises at least a pair of bevel gears which move a cushion holder in a translation movement through at least one screw-nut screw coupling.

7. An adjustable lumbar cushion according to any of ^'Claims 1 and 4, characterized in that said adjusting means

(343',354-357) comprises at least two pairs of spur gears and racks which move a cushion holder in a translation movement.