DESK AND GROUP OF SIMILAR DESKS

Abstract: The invention relates to a desk (10), such as a school desk, with a desktop (20) and a stand. The desktop (20) is formed of, in part, a front triangular book support surface (22) which is raisable and lowerable about its long side so that its side edges (22a) in the lowered position each form a front side edge of the desktop (20), and in part a writing surface (21) that is attached to the long side of the book support surface (22). When the book support surface (22) is raised, the entire desk (10) lies within an imaginary circle (C) in the plane of the desktop (20). The desk (10) is especially meant to be placed next to similar desks in different configurations. Especially, groups of four desks can be configured for either group work or individual work.

Description: DESK AND GROUP OF SIMILAR DESKS Technical Area The subject invention relates to a desk, especially for but not limited to school environments, comprised of a stand and a desktop supported by the stand. The desk includes preferably also an integrated chair. The desk according to the invention is meant to be placed together with other desks of the same type in different configurations. Technical background Traditional classroom furniture arrangement in rows and columns is not ideal since the students see the backs of other students' heads or don't see them at all. Even if the desks are arranged in a horseshoe most students will be sitting ergonomically incorrectly, turned at an angle towards the teacher. Neither iε the use of large round tables an acceptable solution since many students will be sitting with their backs to the teacher. Another disadvantage of the traditional classroom furniture arrangement iε that it is not possible to vary the sitting position to any real extent, and that the furniture is relatively low which is a disadvantage for both student and teacher. FI 29 902 describes a desk comprised of a stand and a desktop supported by the stand. The desk includes an integrated chair. The desktop has a triangular form, and four desks are meant to be positioned opposite each other during group work sc that the desktops can be next to each other. Summarv of the Invention The purpose of the invention is to correct the above-mentioned disadvantages of traditional school furnishing. It should be emphasized, however, that the use of the desk is according to the invention not limited to schools. A particular purpose of the invention is to provide a desk that makes it possible to easily and quickly shift the furniture arrangement between individual work, traditional teaching, group work, discussion, and so on. To achieve these purposes and other advantages is put forward by the invention a desk according to patent claim l, as well as a group of desks according to patent claim 16. The submitted embodiments of the desk are described in the non-independent patent claims 2-15. The submitted, not-restricting embodiments of the invention will now be described in more detail with reference to the attached drawings. Figure descriptions Fig. l is a perspective view of the first submitted embodiment of a desk according to the invention. Fig. 2 is a rear view of the desk in Fig. l. Fig. 3 is a side view of the desk in Fig. l. Fig. 4A is a perspective view of the desktop of the desk in Fig. l. Fig. 4B is a bottom view of the bottom of the desktop in Fig. 4A. Fig. 5 is a top view of the desk in Fig. 1 with the stand omitted. Fig. 6A is a perspective view of the stand of the desk in Fig. 1. Fig. 6B is a top view of the stand in Fig. 6. Fig. 7 is a broken-out side cross section of a footrest arrangement and a moving device of the desk in Fig. l, seen from the side along line Vii-VII in Fig. 8. Fig. 8 is a broken-out cross section of the footrest arrangement, seen in a larger scale from above along line VIII-VIII in Fig. 7. Fig. 9 is a broken-out side view in a larger scale of the moving device in Fig. 7. Fig. 10 is a broken-out cross-section from the front, that shows the seat mounting of the desk in Fig. l. Fig. ll is a perspective view of another submitted embodiment of a desk according to the invention, including a storage drawer. Fig. 12 is a side view of the desk in Fig. ll. Fig. 13 is a perspective view of a desktop with drawer of the desk in Fig. 11 Fig. 14 is a bottom view of the bottom of the desktop and drawer in Fig. 13. Fig. 15 is a broken-out side view in a larger scale of the desktop and drawer in Fig. 13. Fig. 16 is a schematic top view that visualizes four desks according to Fig. 1 or Fig. 11, arranged in a first configuration. Fig. 17 is a schematic top view that visualizes four desks according to Fig. l or Fig. ll, arranged in a second configuration. Fig. 18 is a schematic top view that visualizes five desks according to Fig. l or Fig. ll, arranged in a third configuration. Description of the Submitted Embodiments Figs, l to 10 show a first embodiment of a desk according to the invention. The same identifiers are used for the same parts throughout the figures. The desk shown is especially, but not exclusively, useful as a school desk in a classroom and is designed with particular account taken of the different needs found in such an environment, such as use for both individual work and group work, ergonomics, adjustability for different students, room cleaning, durability, etc. The desk, identified by 10, has as main components a desktop 20, a stand 40, and an integrated seat 50. These three main components will now be described individually. Desktop As seen best in Fig. 3, 4A, and 4B, the desktop 20 is composed of a writing surface 21 and a book support surface 22 that can be raised and lowered, which are held together by a lower connection plate 23. The back of the latter is solidly attached to the bottom of the writing surface 21, while the front is movably attached via a piano hinge 23c to the book support surface 22. The book support surface 22 has the form of an equilateral right-angle triangle, the point of which forms the forward point of the desktop 20, and whose short sides when in folded down position form the two front side edges 22a of the desktop 20. The desktop 20 in the illustrated embodiment is symmetrical about a vertical mid-plane P through the desk (Fig. 4B) . The book support surface 22 can be positioned to the desired angle using a sawtooth-formed arm 23d. The writing surface 21 can be made of any appropriate durable material, and the book support surface 22 is preferably made of the same material in order to form a unified work surface together with the writing surface 21 when folded down. The writing surface 21 has two circularly curved side edges 2ia that form part of a circle C (Fig. 5) with center 0. In the illustrated embodiment the radius of circle C is approximately 40 cm. Each of these two circularly curved side edges 21a ends at the front in a short straight side edge 2lf, which when the book support surface is folded down forms a rear extension of the εide edge 22a. The forward limit of writing εurface 21 is a straight edge 2lb that connects with the forward ends of edges 21f. Instead of completing the circle at the rear, the two circularly curved edges 2ia become a central rear inwardly-curved recesε 2lc (Fig. 4A) towardε the center O in the rear edge of the writing surface 21, so that two armrests or side work εurfaceε 2id exiεt between recess 2ic and the side edges 2la. The forward edge of recess 2lc forms a circular curve in this embodiment. In the illustrated embodiment the center of circle 0 lies inside writing surface 21 very close to receεε 2ic. It is, however, possible to design writing surface 21 differently so that center O lies outside the rear edge of the surface. Thanks to recess 2ic, the seat 50 can be placed completely within circle C (Fig. 5) , which especially has the advantage of allowing unlimited turning of the desk 10 with respect to adjacent deskε of the same kind. It should, however, be noted that the seat back 52 in certain adjustment positions can lie somewhat outside circle C. Importantly, it is possible when necessary for the entire seat 50 to lie within circle C. The entire desktop 20 haε a fixed height next to the student's stomach, but can be tilted up at the front (Fig. 3) . For this purpose writing εurface 21 is rotatably attached to stand 40 via two mounts 24a. Deεktop tilt is adjustable using a swingable mounting 24b. Identifier 2le referε to a support that restε against stand 40 when desktop 20 is lowered. An advantage of having a fixed height for the rear part of desktop 20 is that it makes it easier to group several desks 10 into a larger work table. The following should be noted regarding the diameter of circle C (Fig. 5) that limits the side to side dimensionε of the deεk. In the illustrated embodiment circle C is the circle that defines and in this manner coincides with the circularly-curved side edges 2la of writing surface 21. In Fig. 5, the dashed lines indicate possible back extensions Ll and L2 that are tangent to circle C. The connection plate 23, which forms the bottom of pencil groove 25, alεo has a circularly-curved forward edge 23b (Fig 4B) , but since this edge 23b for reasonε of εuitability εtartε at the ends of the front edge of pencil groove 25, the circularly-curved edge 23b will be defined by a marginally larger circle. In this embodiment the last- mentioned radius increaεes from approx. 800 mm to approx. 808 mm. This forward displacement of the circle at the front part of desk 10 has, however, a negligible effect on whether adjacent desks bump into each other when they are turned, since during use it is not probable that the desks will be turned about an exact center O. ith reference to this, it applies generally to the invention, and especially its definition in the patent claim, that reference to statements of the type "lies completely within the circle" and similar expressions shall be assumed to also include cases where some parts of the desk lie slightly outside C but, however, within the larger circle defined by edge 23b. Stand The stand 40 (Figs. 2, 3, 6A, and 6B) in the submitted embodiment is built up of two mirror- symmetrical steel tubing halves 41v, 41h, that are asεembled together, of which each consistε of the following sections in sequence starting at the top: an upper, εtraight horizontal section 4la; a front vertical post 4lb; a base consisting of a lower straight horizontal section 4lc and a lower inward-curved horizontal section 4ld; an upward-forward leaning (approx. 28°) seat mounting section 4ie approximately half aε long as vertical post 41b; and a downward- forward leaning (approx. 12°) footrest mounting εection 4if approximately as long as seat mounting section 41e which ends in a lower end 4lg immediately above the lower limiting plane of the desk. The εtand halves 4lv, 41h are connected together along symmetry plane P using three bolts 42 in mounting sectionε 4le and 4lf. Aε best seen in the rear view in Fig. 2, the two seat mounting sections 4le diverge upwards from a mutual distance of approx. 10 mm to approx. 20 mm. This applies similarly to the two forward mounting sectionε 4lf. A horizontal curved tube 43 connects together the vertical postε 41b at the top. A certain mutual solidity of halveε 4lv, 4ih iε also achieved through having the back ends of horizontal sectionε 4la mutually connected via rear hinge mount 24a and writing surface 21 mentioned above. As seen in Fig. 6B the baεe (4ic, 4ld) of stand 40 has a relatively large extension sideways as compared with traditional furniture (separate table and chair) , which especially makes desk 10 more stable from the viewpoint of tipping aε compared with known deεkε with integrated seats. The sideways dimensionε of stand 40 are, however, limited such that the εtand lies completely within circle C. Another advantage of the illustrated stand 40 is that the entire desk 10 can be made relatively high, which is good both for the student'ε εitting poεition (εtraight back and open hip angle) and for the teacher standing alongside who due to thiε doeε not have to bend his or her back. The relatively high height also makes it possible to adjust the seat and footrest heights within wide limits as described below. An additional advantage of stand 40 is that seat 50 can be integrated in desk 10. This gives advantages such as simplified turning of the desk, regrouping of desks in the clasε room, elimination of chair scrape on the floor, etc. The manufacturing cost of stand 40 can be kept at a low level in spite of all the stand'ε advantages. Seat Seat 50 is, as stated above, integrated in desk 10. The seat bottom 51 and seat back 52 are together rotatable about a vertical rotation axis A (Fig. 5) . Seat 50 is mounted in the area between the forward edge of recess 2lc and circle C. Seat 50 including seat back 52 can thus be completely within circle C, which has the advantage that the student can turn himself or herself in different directions relative to the desktop without risk of bumping into adjacent desks. Thanks to the side armrests 2ld the student has at least some work surface in front of him or her even if seat 50 is turned sideways. In the illustrated embodiment the side armrests 2id limit the rotation angle of the seat when seat back 52 bumps into side armrest 2id. Figs. 2, 3, and 10 show how seat 50 is mounted on stand 40. The seat bottom 51 has a seat plate 5ia on whose underside somewhat behind the crosswise mid-line of seat bottom 51 (see Fig. 3) are mounted two rubber shock absorbers 51b with mutual distance through bolts 5lc. Each rubber shock absorber 5lb contains a nut at the top and a bolt at the bottom, of which the latter is held by nut 5lh in lower εupporting plate 51d. Aε εhown in Fig. 10, the bolt in rubber εhock abεorber 51b lieε outεide of the side edge of supporting plate 5ld and therefor can be moved forward-backward to the desired position, so that seat bottom 51 can be fixed in position relative to supporting plate 51d using nut 51h and half-circular washer 51g. In a straight tube 5le, which is welded to the underside of supporting plate 51d concentric with rotation axis A, an upper vertical section 53a of a seat mounting tube is rotatably inserted, where 55a refers to a thrust bearing and 55b refers to a sleeve bearing. The lower section 53b of the seat mounting tubing leans in the same direction as the seat mounting section 4le of stand 40, that is, approx. 28° from the vertical plane, and is attached in the space between these two mutually diverging seat mounting sections 4le. For this purpose, a bolt equipped with a height-setting wheel 54c is put through the mentioned lower section 53b, through seat mounting sections 4le and through a hole in a separate angle iron 54b, in order to connect with nut 54a that self-lockε in the inner angle of angle iron 54b. When drawn tight the outside of the angle iron is pressed against the seat mounting sections 4ie. Thanks to the fact that seat mounting sections 4le lean forwards-upwardε, and that εeat mounting tubing 53b iε diεplaceable in the εame direction, a εhorter perεon automatically comeε cloεer to desktop 20 when the seat is raised. This mounting and displaceability greatly simplify the positioning of the seat 50 relative to the desktop 20. Thanks to the fact that seat mounting sections 4ie diverge upwards from each other, the seat 50 can be firmly positioned at the εelected height. The more weight there iε on the seat the firmer it is held in place, since any backwards-downwards displacement of mounting tubing 53b results in it being automatically displaced backwards-upwardε, that iε, in the direction of the force exerted by bolt 54c. There iε, however, no risk of undesired locking of stand 40 to the seat mounting tubing 53b, because the latter can move freely backwards-upwards away from stand 40 as soon as bolt assembly 54a/54c is looεened. The seat back 52 is mounted uεing an upwards- backwards leaning mounting tubing 52a which is welded to the back of straight tube 51e and in which is inserted a downwards-forwardε bent section of support tubing 52b. Footrest The deεk in Figs. 1-10 iε also furnished with a footrest arrangement (see especially Figs. 1, 3, 7, and 8) that is displaceably mounted on downward-forward leaning footrest mounting sections 41f which are part of stand 40. The footrest arrangement includes a front footrest and a rear footrest. The front footreεt iε made of a support arm 44a which lies in symmetry plane P and which at the front supports a transverse footrest tube 44b. Support arm 44a is angled upwardε 90U at the rear and is attached using bolt 46a to the upwardly diverging εpace between footrest mounting sections 4lf (Fig. 8) . When necessary, if the student is short, the front footrest can be rotated 180U upwards relative to the position in Fig. 7. The rear footrest is made of a transverεe footrest tube 45b which is welded to an angle iron 45a. The point of angle iron 45a is inserted in the diverging space between the footrest mounting sectionε 41f, and the above-mentioned bolt 46a pasεes through the point of angle iron 45a and is threaded in nut 46b which, similarly to the seat mounting above, self-locks against the inside of angle iron 45a. The furnishing of double footrests fosters an ergonomically varied sitting position. The space between the footrest mounting sections 4lf of stand 40 divergeε upwardly from each other for the εame reaεon aε for the εeat mounting. Similarly, that the footreεt mounting sections lean upward-backward resultε in an automatic compensation of the horizontal poεition of the footrest when it is adjusted in height--a short student automatically has the footrest nearer to the rotation axis of seat 50. It can be seen that desk 10, thanks to the above- described principles for mounting and adjustment of the seat and the footrest, can be used for people of all ages. Moving device As mentioned above, it is easy to turn or move desk 10 to new groupings thankε to the fact that deεktop 20 and εeat 50 are integrated with each other. To further simplify this, desk 10 has a central moving device referred to generally by 47. This is shown in detail in Figs. 7 and 9. Moving device 47 is composed of a moving wheel 47a that is rotatably bearing-mounted on a raiεable-lowerable pivoting wheel arm 47b. heel arm 47b iε pivotably mounted for movement in symmetry plane P in the lower end 41g of stand 40 via joint pin 47c (which here can be one of the boltε 42) . A εtop 47d limitε the frontward rotation of wheel arm 47b. When desk 10 standε on the floor aε in Fig. 3, the moving wheel reεts lightly on the floor as in Fig. 7. When desk 10 is to be moved and/or turned, the desk is lifted somewhat, for example, at the front, high enough so that wheel arm 47b with wheel 47a fall down to the moving position shown in Fig. 9. Desk 10 will then rest partly on wheel 47a and partly on parts of the base of stand 40. In this position it is easy to maneuver the desk to the correct position, for example, by lifting slightly the back part of the desk. When in the moving position as in Fig. 9, also cleaning under desk 10 is made easier, and it can be seen that such a cleaning-simplifying construction does not necesεarily require using moving wheel 47a but only a raisable-lowerable support with which the desk can be placed in a raised position from the floor. Group ingε Referring to Figε. 16-18, three poεεible ways to group desk 10 according to the above-described embodiments are illustrated. For the sake of clarity, both stand 40 and seat 50 are omitted. Fig. 16 shows a group of four deskε lOa-lOd, with the same construction as the above-described desk 10, arranged in a first configuration for group work or similar. Desks lOa-lOd lie, as before, each within itε circle C as in Fig. 5, and the desks are placed so that the centers O of the related circles lie each in a separate corner of a square and so that the four circles are tangent to each other. In thiε firεt configuration in Fig. 16, all deεktopε 21 and book support surfaceε 22 are preferably folded down. Deεks lOa-lOd are turned towards a common central point so that the four book εupport εurfaceε 22 together form a εquare which iε part of a larger work area formed by the four deεktops 20. It can be seen that the fixed desk height at the back edge of the writing surface 21 is a factor that facilitates this configuration. It should also be noted that this grouping, compared with grouping of traditional rectangular desks, is advantageous because the students sit in a circle and can see each other better. Fig. 17 shows the same group of desks lOa-lOd, but now placed in a second configuration for individual work. Compared to the configuration in Fig. 16, each desk has now been turned about its own circle center O in varying degrees. Thanks to the fact that each desk 10 lies within its own circle C, and that these circles are only tangent to each other, it becomes possible to by only rotating the desks switch between these two configurations. It can be seen that the book support surfaces 22 are preferably in the upright position during such movement. Fig. 18 shows a group of five deskε 10a-lOe, arranged in a third configuration for group work. This configuration can naturally be used for both more and fewer desks than five. In this configuration, the students can especially turn towards their neighbors and even εo have a writing surface--armrest 2ld--in front of them, thanks to the design of the desktop 21. Embodiment With Drawer Figs. 11-15 εhow a second embodiment of a desk according to the invention, which is mainly identical to the desk in Figs. 1-10 except that it has a drawer that is open at the top under desktop 23. The components that are identical in the two embodiments have the same identifiers, and a repeated deεcription of theεe components is not provided. Drawer 30 extends under both the writing surface 21 and the connection plate 23, and has a form that at the rear meets with recesε 2lc and at the front meetε with the curved front edge 23b of the connection plate 23. Drawer 40 lies thusly completely within circle C. Aε illustrated in the bottom view in Fig. 14, the sideε of drawer 30 lean slightly outwards and at the top they merge into a horizontal mounting and support flange 31, where connection plate 23 is firmly attached to flange 31. Writing surface 21, which here acts as a cover, is at itε front edge 2lb pivotably connected with connection plate 23 via a piano hinge 32 and can be placed in a raised position uεing a liftable arm 33 as shown in Fig. 15. In the folded-down position, the rear part of writing surface 21 rests on drawer 30. Drawer 30 leans downward-forward so that writing surface 21 is horizontal in its folded-down position (Fig. 12) . The book support surface 22 is raisable and lowerable iε the same way as has been described earlier. Furthermore, the entire drawer 30 can be set at one or more different angles relative to stand 40 (not shown) because the drawer is pivotably mounted at the rear of its sides via bolt 34, which is mounted in the rear ends of horizontal arm sections 4la. In the folded-down position, drawer 30 rests on horizontal curved tube 43, and in the raised position a support arm 35 (not additionally described) iε lifted up to support the drawer. It can be seen that this embodiment with drawer can be arranged in the same configurationε as the first embodiment, and that desks with and without drawers can be used at the same time within the same' group.

Claims: PATENT CLAIMS l. Desk (10) including a desktop (20) and a frame or stand (40) , characterized by that the desktop (20) iε formed by in part a forward book support surface (22) in the form of an equilateral triangle which is raisable and lowerable about its base so that its sides (22a) in the lowered position each form a front side edge of the desk top (20) , and in part a writing surface (21) that is attached to the base of the book support surface (22) , and that the desktop (20) with its book support surface (22) raised lies mainly inside an imaginary circle (C) in the plane of the deεktop (20) , which circle (C) doeε not cross the two front side edges or the imaginary rear straight-line extensions (Ll, L2) of the desktop (20) , such that the book support surface (22) in the lowered position crosses the above-mentioned circle (C) and in its raised position lies within the above-mentioned circle (C) . 2. Desk (10) according to claim 1, characterized by that the named equilateral triangleε are right-angle triangles. 3. Desk (10) according to claim 1 or 2, characterized by that the writing surface (21) iε delimited at the front by a εtraight front edge (21b) parallel with the base of the book support surface (22) and is delimited at the sides by outwardly curved, curved side edges (2la) which form the rear side edges of the desktop (20) . 4. Desk (10) according to claim 3, characterized by that the outwardly-curved, curved side edges (2ia) of the writing surface (21) are circularly curved and coincide exactly or for all practical purposeε exactly with the above-mentioned circle (C) . 5. Desk (10) according to claim 4, characterized by that the imagined rear straight extensions (Ll, L2) of the front side edges of deεktop (20) each form a tangent to the circularly-curved edges (2la) of the writing surface (21) . 6. Desk (10) according to any of the above claims, characterized by that the rear peripheral edge of the writing surface (21) forms a forward-going recess (21c) in writing surface (21) for a user, which recesε (2lc) iε delimited on the εideε by two armreεt-forming εurface εections (2ld) of the writing surface (21) . 7. Desk (10) according to any of the above claimε, characterized by that the deεktop (20) further includeε a lower connection plate (23) , which connects together the writing surface (21) and the book support surface (22) and which lies within the above-mentioned circle (C) , εuch that the book support surface (22) is movable attached (23c) with the connection plate (23) and rests against its upper side in its folded-down position. 8. Desk (10) according to claim 7, characterized by that the writing surface (21) and the book support surface (22) between themselves delimit a pencil groove (25) , so that the lower connection plate (23) forms a bottom for the pencil groove (25) . 9. Desk (10) according to any of the above claims, characterized by that the entire desk (10) , including the stand (40) , is situated completely within the above¬ mentioned circle (C) . 10. Desk (10) according to any of the above claims, characterized by that the stand (40) is formed of two mirror-symmetrical side halves (4lv, 41h) , such that each side half (4lv, 41h) has an upper horizontal section (4ia) that supports the desktop (20) , a front post (4lb) and a lower horizontal section (4lc) which is meant to rest on a floor. 11. Desk (10) according to any of the above claims, characterized by that the desk further has a seat (50) borne by the stand (40) , which also is located completely within the above-mentioned circle (C) . 12. Desk (10) according to claim ll, characterized by that the εeat (50) iε adjuεtable relative to the stand (40) in a direction obliquely upward-forward, so that a height adjustment of the seat (50) relative to the stand (40) results in an automatic compensation of its horizontal position relative to the desktop (20) . 13. Desk (10) according to claim 12 in combination with claim 10, characterized by that the lower horizontal arm (4lc) of each side half (4lv, 4lh) at its rear end becomes a rear arm (4ld) , which leads in towards a vertical mid-plane (P) of the desk (10) and at thiε mid-plane becomes an obliquely upward-forward leaning seat mounting section (4ie) on which the seat (50) is displaceably mounted via a εupport arm (53a, 53b) . 14. Deεk (10) according to claim 13, characterized by that the upward-forward leaning εeat mounting εection (4le) becomes a downward-forward leaning footrest mounting section (4if) , on which a footrest (44; 45) is displaceably mounted εo that an adjuεtment of the footreε (44; 45) height poεition relative to the εtand reεults in an automatic compensation of its horizontal position relative to the seat. 15. Desk (10) according to any of the above claimε, characterized by that the εtand (40) has at the bottom a raisable-lowerable moving wheel (47a) εituated near a vertical line through the center (O) of the above¬ mentioned circle (C) . 16. Deεk (10) according to any of the above claimε, characterized by that the desk (10) further has a drawer (30) which iε located under and supportε the deεktop (20) and which haε the writing εurface (21) aε a raiεable cover. 17. Group of a number of deεkε (lOa-lOd) according to any of the previouε claimε, εuch that both the above- mentioned triangle and circle (C) are of equal εize for each of the group's four desks (lOa-lOd) , and such that the top angle of each triangle is equal to 360U divided by the number of deskε in the group, which desks are so placed that their circles (C) are tangent to each other, so that the group's deskε can be placed in a firεt configuration (Fig. 16) where the book εupport εurfaceε (22) are folded down and turned towardε each other in order to form together a polygon that is part of a larger continuous work area formed by the writing surfaces (20) of the desks (lOa-lOd) , or in a second configuration (Fig. 17 for individual work through rotation of the deskε with upright book support εurfaceε (22) inεide their reεpective circleε (C) . 18. Group according to claim 17, characterized by that the group conεiεtε of exactly four deεks.

Inventors: DENCKER NILS, DENCKER, NILS
Applicants: DENCKER NILS, DENCKER, NILS
Application year: 1996
Main classification: A47B41
IPC codes: A47B41