US 3535000 A
Description (OCR text may contain errors)
Oct. 20, 1970 P. J. PROTZMANN CANTILEVERED FURNITURE AND JOINTS THEREFOR 3 Sheets-Sheet 1 Filed Feb. 5. 1968 FIG. 2.
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Oct. 20, 1970 P. J. PROTZMANN CANTILEVERED FURNITURE AND JOINTS THEREFOR 3 Sheets-Sheet 2 Filed Feb. 5. 1968 INVENTOR. 2575? ,1 awn/Wu Fae- M,W BY M Anne/vex:
CANTILEVERED FURNITURE AND JOINTS THEREFOR Filed Feb. 5. 1968 P- J- PROTZMANN Oct. 20, 1970 I5 Sheets-Sheet 3 FIG] 0 w 6 T 5 WM WWW p 1 m United States Patent 3,535,000 CANTILEVERED FURNITURE AND JOINTS THEREFOR Peter J. Protzmann, Grand Rapids, Mich., assignor to Herman Miller Inc., Zeeland, Mich., a corporation of Michigan Filed Feb. 5, 1968, Ser. No. 702,955 Int. Cl. A47b 39/00 US. Cl. 297-142 17 Claims ABSTRACT OF THE DISCLOSURE This disclosure relates to a combination seat and table structure in which a single post unit supports a table top and at least one cantilevered seat which is movable about the post toward and away from the table. The seat is mounted by a double jointed structure for both swinging pivotal movement and for rotation about a vertical generally central of the chair. The novel structure automatically biases the seat into a storage position adjacent and parallel to the table and restrains the chair against striking the table as it returns to this position. Preferably there are two seats on each post support and a plurality of post supports, each support fixedly attached to the floor and a single length of table top.
This invention relates to cantilevered furniture and joints therefor. In one of its aspects it relates to a furniture construction in which a seat is supported by a cantilevered member and the cantilevered member is supported by a joint which permits rotation of the cantilevered member relative to a fixed support, the joint having a bracket member receiving the joint, a housing means positioned within the bracket and rotatable therein, means rotatably attaching the bracket member and the housing, rotation limiting means within the housing and associated with the bracket member to limit the extent of rotational movement between the housing and the bracket, and biasing means within the housing to bias the housing at one end of the rotational position allowed by the motion limiting means so that the seat will always be in a given position when not in use.
In another of its aspects the invention relates to a furniture joint construction for chairs and the like wherein a pintle is axially rotatable within a housing, yieldable means support the pintle within the housing and urge the pintle in an axial direction, cam and cam follower means between the housing and the pintle limit the rotational motion of the pintle relative to the housing when the pintle is in a given axially position and urge the pintle into a predetermined relationship relative to the housing in a second given axially position. In a practical application in which the joint is used to support a seat, the seat would be freely rotatable when in use but would be urged to a predetermined position, for example, relative to a table, when the seat was not in use.
Since the days of the one-room school, the combination of a seat and desk top has been known. Early models were fixed structures in which a seat or bench had supporting members for individual desk tops. These early models were inflexible and cumbersome. Oftentimes the desk tops were inadequate in size.
Attempts have been made to simplify the early structure and to provide adequate writing surface for the student. To this end, Sheldon, 1,892,813, discloses a two desk unit having a pair of table tops, four supporting legs, two of which are positioned in the front central portion of the unit. Each of the front legs supports a rotatable seat support which in turn contains a rotatably Patented Oct. 20, 1970 See mounted seat. The extent of rotation of the seat on the support and the extent of rotation of the seat support member are limited such that when the back of the seat is parallel to the edge of the table, the seat will not strike the table edge.
Although the above unit was an advance in the art and suitable for many purposes, it is cumbersome and expensive in that four legs are required to support the structure. Further, the nature of the use of these structures, i.e., by students, will most likely result in a sloppy appearance, due to the fact that the seats will be left in various positions. Further, the soaring cost of education necessitates that a desk construction be as efficient as possible.
It is known to support a continuous work surface 'with a plurality of posts which also support seats, which seats are rotatable toward and away from the work surface. It is desirable that the seat is rotatable on a cantilevered arm toward and away from the table top and biased in a position near the edge of the table, but is prevented from striking the table. It is further desirable that the seat be rotatable relative to the cantilevered arm and that when the seat is not in use, the seat will have a neat appearance in relation to the desk. The present application deals with structures which can be used to limit the rotation of the seat and cantilevered arm and which structures biases the arm and seat in an orderly position adjacent the table top when not in use.
By various aspects of this invention, one or more of the following, or other, objects can be obtained.
It is a still further object of this invention to provide a table top and seat arrangement whereby the need to straighten or position seats to create a uniform appearance when the seats are not in use is eliminated.
It is a further object of this invention to provide a joint structure for two members which limits the rotation of one member relative to the other and which biases the one member in a given position relative to the other without any extraneous stops.
It is a further object of this invention to provide a joint structure in which a certain degree of unrestrained relative rotation is permitted between two members in one position and one of the members is biased in a given position relative to the other member in a second position.
It is a further object of this invention to provide a joint for a chair seat wherein the seat is freely rotatable on a support when occupied, but which returns to a given position relative to the support when it is unoccupied.
Other aspects, objects, and the several advantages of this invention are apparent to one skilled in the art from a study of this disclosure, the drawings, and the appended claims.
According to the invention, a seat is supported by a cantilevered member such that the cantilevered member is rotatable relative to a support and the seat is pivotably supported by the cantilevered member. The joint between the cantilevered member and its support comprises a bracket and a housing rotatably received by the bracket. The housing contains rotation limiting means which are associated with the bracket to limit the extent of relative rotation between the bracket and the housing. Biasing means are also provided within the housing to urge the cantilevered member to a given position relative to its support.
Preferably the joint between the seat and the cantilevered member contains a means to bias the seat in a predetermined position relative to the cantilevered member. The biasing means are such that the seat is free to rotate, at least through a limited angle, when the seat is oc- 3 cupied, but urges the seat to the predetermined position when unoccupied.
The invention is advantageously employed in a combination table top supported by a plurality of vertical pillars each of which also supports one or more cantilevered seats. The biasing means and rotation limiting means can be so positioned that when the seat is not occupied it will be biased in a position wherein the seat back will be closest to the edge of the table top without striking the same, and the back of the seat will be parallel to the edge of the table top.
The invention will now be described with reference to the accompanying drawings in which:
FIG. 1 is a perspective view of an embodiment of the invention;
FIG. 2 is a rear elevational view of the embodiment shown in FIG. 1;
FIG. 3 is a side elevational view partly in cross section of the embodiment shown in FIG. 1;
FIG. 4 is a top view of the embodiment shown in FIGS. 1, 2 and 3, showing the rotational position of the seats;
FIG. 5 is a sectional view through one of the joints between the chair supporting member and the post support member;
FIG. 6 is a sectional view along lines VIVI of FIG. 5;
FIG. 7 is a sectional view of the joint between the seat support member and the seat bottom; and
FIG. 8 is a perspective view of a cam member shown in section in FIG. 7.
Referring now to the drawings and especially to FIGS. 1 through 4, there is provided a table top or writing surface 2 at which is positioned a plurality of seats 4. A plurality of post support members 6 supports the seats through cantilevered arms 10 and also supports the table top 2. A recess bracket 14 is attached to post support members 6 and rotatably supports cantilevered arm 10. Suitable fastening means fix the bracket 14 to the supporting post 6. Thus, a table top and seat unit comprising a table top and seat is supported by a single post support 6. As can be seen in FIG. 4, the cantilevered arms 10 are rotatable about a point on supporting post 6. The seats are also rotatable about the joint between the cantilevered arms 10 and the seats 4. According to one embodiment of the invention, a means is provided to bias the seat cantilevered arm 10 in a position such that the seats are closest to the table. Means are further provided to prevent the cantilevered arm 10 from rotating in a direction toward the table to a point where the seat will strike the table. There is provided a means to bias the seat on the cantilevered arm 10 such that the line of the back of the seat is parallel to the edge of the table top as shown in FIGS. 1 and 2. Thus, with the use of the invention, when the seats are not in use, they will automatically return to the position shown in FIGS. 1 and 2, i.e., with the backs of the seats close to, but not touching the table edge, and with the line of the back of the seats parallel to the edge of the table. In a room where multiple seats are employed with a table, an orderly appearance will prevail without the need for individually straightening the seats.
Referring now specifically to FIG. 3, the supporting post has a rectangular flange 26 attached to the bottom thereof. The flange 26 is rigidly attached to the floor structure through screw member 28 and suitable fastening attachments for the screw. The table top supporting structure is substantially vertical with a supporting bracket 12 at the upper portion thereof beneath and attached to the table top 2. As is appreciated by one skilled in the art from an inspection of FIG. 3, the moment created in a counterclockwise direction about the bottom of supporting pillar 6 by a student positioned in a seat 4 away from the desk top 2 is counterbalanced by a moment in the clockwise direction, due to the weight of table top 2 acting through supporting member 8. The structure is, therefore,
somewhat balanced when at least some of the seats are occupied.
Referring now to FIG. 2 specifically, it can be seen that a moment created by a student sitting, for example, in seat 4a, will be counterbalanced by a student sitting in 412. Further, when supporting posts 6 are rigidly attached to the floor, there is formed a box structural member, comprised of the floor, the table top 2, and adjacent supporting post 4. Thus, the moment given to the unitary structure by, for example, a student sitting in seat 4a will be counterbalanced by a moment produced by a student sitting in 4b. Whereas it is recognized that a student will not sit in each seat, it is to be noted that when the arrangement is such that a long table top has a plurality, for example ten or twelve, of supporting posts, each having two seats, then on a statistical basis, there will be about as many students sitting on the right side of the posts as on the left side of the posts.
As is appreciated by one skilled in the art, the use of a minimum number of supporting posts not only reduces the cost of the structure, but also facilitates in cleaning the floor under the chairs and table.
Referring now again to FIG. 4, the cantilevered arm 10 is supported through a novel joint structure comprising a cylindrical annular housing 20 which is positioned rotatably between a bracket 14, having an upper horizontal flange 16 and a lower horizontal flange 18.
The chair 4 is attached to a chair support 24 which is rotatably in a second novel joint structure within cylindrical housing 22. The cantilevered arm 10 is attached to the cylindrical housing 22.
A detailed sectional View of the joint between the cantilevered arm 10 and the recessed bracket 14 is shown in section in FIG. 5. With reference now specifically to FIG. 5 and FIG. 6, cylindrical housing 20 has firmly attached to the inner portion thereof, a core member 32 having a downwardly extending portion having a flat, vertical surface 38. Core member 32 also has a vertical hole 36, in which is positioned one end of spring 44. A bearing member 28 is positioned beneath the lower portion of core 32 and is fixed to the inner surface of cylinder 20. A second bearing member 26 is positioned below bearing 28 and provides for a low friction rotation between bearing 28 and bearing 26, and between cylinder 20 and bearing 26. Flange 18 has a vertical hole therethrough, in which is positioned a pivot point shaft 30 having an upwardly extending portion with a pair of beveled surfaces 34 and 35 (FIG. 6) spaced from the inner wall of housing 20. As can be seen in FIG. 6, the rotation of core 32, which is attached to cylindrical housing 20, is limited by the angle a, which is preferably about 70". Thus, the combination of pivot point core 30 with surfaces 34 and 35 and core 32 with surface 38 limits the rotation of the seat supporting member 10, such that the seat, when its back is parallel to the edge of the table top, will not strike the table. Further, the combination also limits the rotation of the seat supporting member 10 such that the seat on one side of the supporting post 6 will not strike the seat on the other side of the supporting post 6. Obviously, there must be sufficient rotation to permit comfortable ingress and egress of students to their respective desks.
Spring alignment rod 42 is positioned within spring 44, and is at the lower portion thereof, is positioned in hole of core 32. At the upper portion of the spring alignment rod 42, it is positioned within a recessed portion 47 of an upper fitting core 46. The upper end of spring 44 is positioned in hole 50 of core 46. Bearing member 48 provides relatively frictionless movement between core 46 and bearing 48. A screw member 56 is threaded in core 46, and draws core 46 against a tooth lock washer 54 to hold upper core member 46 fixed.
The shaft 30 is secured to flange 18 by drilling a hole through the flange 18 and through the shaft 30 when the seat 4 is in the desired return position and the surface 35 is positioned against surface 38. A pin 58 is then inserted through the shaft 30 and flange 18.
In operation, as seat support member rotates flange 16 through screw member 56 and lock washer 54 holds upper core member 46 and the upper end of spring 44 stationary. Since the bottom portion of spring 44 is positioned with lower core member 32, it rotates with seat support member 10 and cylindrical housing 20. The 1'0- tation of seat support member 10 is limited by the abutment of surface 38 of core 32 against either surface 35 or surface 34 of pivot shaft 30.
Referring now to FIG. 7, seat support 24 is rigidly attached to seat 4 and has a pintle attached thereto by a slot and tooth arrangement or other suitable attaching means, such as a pin. The pintle 60 extends down into a cylindrical housing 22, which is rigidly attached to the seat supporting member 10. A bearing member 16 permits relatively frictionless rotation of swivel shaft 60 within cylindrical housing 22. At the lower portion of cylindrical housing 22, inwardly extending flange members 64 or a continuous weld (not shown) supports plate 66, which in turn supports spring member 70, shock absorber 72, and plate 68. Plate 68 supports ball 74, which is positioned in an indentation 76 in swivel shaft 60.
The rotation of swivel shaft 60 is limited by a cam formed from annular sleeve 78, which is fixedly attached to cylindrical housing 22 through pin 82. A cam follower pin 80, attached to swivel shaft 60, contacts the cam surface and limits the rotation of the swivel shaft, and in turn, limits the rotation of the seat on the seat supporting member.
The cam sleeve 78 can be more clearly seen in FIG. 8. The cam sleeve 78 comprises an annular cylinder having a portion of the wall cut out. The cam surface is comprised of sections 84 to 86 to 88. When the cam follower pin 80 is positioned at point 86, the seat will be positioned such that the back of the seat is parallel to the line or edge of the table when the seat is nearest the table. As the seat is turned, for example, in a clockwise direction as seen in FIG. 4, the cam follower pin 80 will move from position 86 to 88 in the cam sleeve 78. Conversely, as the seat is rotated in a counterclockwise position as seen in FIG. 4, then the cam follower pin will move from point 86 to point 84 in the cam member 78. Preferably, the total angle of rotation is about 140 (from point 84 to point 88). As can be seen from FIG. 7, the spring biases the swivel shaft 30 in the up position, in which position the cam follower pin will be in contact with point 86 of cam member 78. In this manner, when the seat is not in use, the joint will urge cam follower to point 86 to maintain the seat in a predetermined position rela tive to cantilevered arm 10. When the chair is in use, spring 70 will be forced downwardly to permit unrestrained rotation of the chair between the limits prescribed by points 84 and 88 of cam sleeve 7 8.
For purposes of simplicity, the seat and joint has been shown with only a swivel joint, i.e., in which the seat is rotatable about a vertical axis. However, it is within the scope of the invention to use the inventive swivel joint in combination with a tilting shaft wherein a conventional tilt joint is provided in support 24.
Whereas the seat joint finds particular utility in cantilevered furniture as has been described, it is within the scope of the invention to employ the novel joint in other furniture arrangements where for example, the cylindrical housing 22 is fixed in place.
Whereas the invention has been described with relation to a plurality of seats aligned in a relatively straight line along a table surface having a relatively straight edge, it is within the scope of the invention to provide a plurality of seats along a table top having a curved or circular configuration. The invention can also be employed in the construction of an arrangement in which the line or edge of the table top follows a wavy configuration.
Reasonable variation and modification are possible within the scope of the foregoing disclosure and the drawings of the invention without departing from the spirit thereof.
The embodiments of the invention which an exclusive property or privilege is claimed are defined as follows:
1. In a furniture construction in which a seat is supported by a cantilevered member, said cantilevered member is rotatably supported through a joint, the improvement in the joint comprising:
a bracket member;
housing means positioned within said bracket member and rotatable therein;
axle means fixed to said bracket member and rotatably coupling said bracket member and said housing means;
first and second stop means within said housing, said first stop means being fixed to said axle means and said second stop means being fixed to said housing means so as to limit the extent of relative rotational movement between said housing means and said bracket member;
biasing means within said housing to bias said housing means at one end of the rotational position allowed by said motion limiting means so that said seat will always be in a predetermined position relative to a fixed point when not in use.
2. A furniture construction according to claim 1 wherein said bracket member is fastened to a supporting post and said housing means is aflixed to said cantilevered member.
3. A furniture construction according to claim 1 wherein said bracket member comprises means for attaching said bracket to a supporting member and a pair of horizontal flanges vertically spaced from each other, between which horizontal flanges said housing means is received.
4. A furniture construction according to claim 3 wherein said axle means comprises a shaft attached to the lower of said horizontal flanges, said shaft having one end thereof positioned within said cylindrical housing; connecting means between the upper horizontal flange and the inner portion of said housing; and second stop means comprises a core member fixedly positioned in said housing means, said core member having a downwardly extending portion with a substantially vertical surface spaced from the inner wall of said cylindrical member, an upwardly extending mating portion with a substantially vertical surface on said shaft attached to said lower flange forming said first stop means, said shaft surface being positioned within said cylindrical housing, spaced betwe n said vertical surface of said core member and said cylindrical housing wall, said core vertical surface and shaft surface being so shaped and positioned as to allow limited rotation of said cantilevered arm relative to said bracket.
5. A furniture construction according to claim 4 wherein a table top is supported by a vertical support member, said joint is supported by said vertical support member, and said rotation limiting means prevents said seat from striking said table.
6. A furniture construction according to claim 5 wherein a second joint, a second cantilevered member, and a second seat are supported by said vertical support member, said second cantilevered member extending away from said first mentioned cantilevered member, said second joint containing rotation limiting means and biasing means such that said seats are prevented from striking each other as both rotate towards each other in one limit of rotation and said seats are prevented from striking the table top in the other limit of rotation.
7. A furniture construction according to claim 4 wherein said biasing means comprises a coil spring within said housing having one end affixed to said connecting means and the other end in said core member.
8. A furniture construction according to claim 1 where in a seat joint supports said seat on an outer portion of said cantilevered member, said seat joint having means to permit limited rotation of said seat relative to said 7 cantilevered member and having means to bias said seat in a predetermined position relative to said cantilevered member when said seat is not occupied.
9. A furniture construction according to claim 8 Wherein said rotation limiting means for said seat comprises a cam member affixed Within an annular housing and a cam follower fixed to said seat.
10. A furniture construction according to claim 1 wherein a table top is supported by a vertical support member, said joint is supported by said vertical support member, said rotation limiting means restricts the movement of said cantilevered member so that said seat does not strike said table, and said seat is attached to said cantilevered member through a seat joint which permits limited relative rotation between said seat and said cantilevered member, positioning means are provided Within said seat joint to urge said seat into a position so that the line of the table top is parallel to the back of said seat when said seat is near said table top and not in use.
11. A furniture construction according to claim 10 wherein said biasing means of said joint urges said seat to a position closest to said table top.
12. A furniture construction according to claim 11 wherein a second seat is supported by a second cantilevered member, said second cantilevered member is afiixed to said vertical support member and extends in a direction opposite from that of said first mentioned cantilevered member; means are provided to urge said second seat closest to said table top; means are provided to restrict the motion of said second cantilevered member so that said seat does not strike said table top, and means are provided to bias said seat relative to said cantilevered members so that the back of said seat is parallel to said table top when said seat is nearest to said table top.
13. A joint suitable for seats and the like comprising:
a supporting structure;
housing means attached to said supporting structure;
a pintle axially rotatable within said housing means;
cam means aflixed to said housing means, said cam means including an annular sleeve and an opening in said annular sleeve;
cam follower means attached to said pintle and extending into said opening so that the motion of said pintle is restricted by said cam means, said cam means being so shaped as to permit substantial rotational movement of said pintle relative to said housing when said pintle is in a first axial position within said housing; and to permit relatively little, if any, rotational movement of said pintle relative to said housing when said pintle is in a second axial position upwardly with respect to said first axial position; and
yieldable means supporting said pintle within said housing and biasing said pintle upwardly toward said second axial position whereby said pintle is free to rotate between the limits defined by said cam means when said pintle is depressed to said second position.
14. A joint according to claim 13 wherein said opening is a substantially triangular portion cut from a side wall of said sleeve with one peak of the triangle being axially displaced upwardly from the other two peaks of said triangle, said pintle axially slides within said sleeve and said cam follower is positioned within said out out triangular portion of said annular sleeve.
15. A joint according to claim 13 wherein said pintle is positioned substantially vertically and fixedly connected to the underside of a seat; said housing means is affixed to a rotatable cantilevered member, which cantilevered member is rotatably attached to a support member; a table top is aflixed to said supporting member whereby when said pintle is forced downwardly, said seat is free to rotate, at least through a limited angle; said cam means being so shaped, and said yieldable means having such a strength that in the absence of weight in said seat, said seat will return to a predetermined position wherein said predetermined position is such that the back of said seat is parallel to an outer edge of said table top when said seat is close to said edge of said table top.
16. In combination with a fixed vertical pillar; a horizontally swingable cantilever means to pivotally support a seat from said pillar; said cantilever means comprising:
an arm having at one end a tubular member;
a recessed bracket secured to said pillar having upper and lower horizontal flanges rigidly joined together, said tubular member being received between said flanges; pin-like elements fixed to said flanges and extending axially toward each other from said flanges into said tubular member, said pin-like elements supporting said tubular member and about which pinlike elements said tubular member can rotate;
a two-member stop within said tubular member, one member of said stop being secured to said tubular member and the other member of said stop being attached to one of said pin-like members; said stop members limiting the rotational movement of said tubular member with respect to said recessed bracket to a given are;
means biasing said arm to one limit of its rotation.
17. The combination recited in claim 16 wherein a table is mounted on said pillar and a seat on the other end of said arm; said seat at said one limit of its rotation being adjacent and parallel to said table.
References Cited UNITED STATES PATENTS 2,329,697 9/1943 Davies 248417 X 3,076,677 2/1963 Kelso 297142 3,116,088 12/1963 Thaxton 248-417 X 3,212,816 10/1965 Nordmark 248-4l7 X 3,262,733 7/1966 Black et al 297-142 3,385,550 5/1968 Doerner 248417 X 3,419,305 12/1968 Baran 248417 FOREIGN PATENTS 508,529 12/1954 Canada.
JAMES T. MCCALL, Primary Examiner U.S. Cl. X.R.