US3702204A

US3702204A - Modular seating assembly

Info

Publication number: US3702204A
Application number: US72416A
Authority: US
Inventors: Max E Tipton; Wilmer R Schultz
Original assignee: Wilmer R Schultz
Current assignee: American Seating Co
Priority date: 1970-09-15
Filing date: 1970-09-15
Publication date: 1972-11-07
Anticipated expiration: 1989-11-07

Abstract

MODULAR SEATS MOLDED OF PLASTIC MATERIAL ARE SECURELY SUPPORTED ON AN ELONGATED FRAMEWORK BY FASTENERS EXTENDING BETWEEN AND ABUTTING THE ADJACENT SIDE EDGES OF THE SEATS WHILE SERVING TO ACCOMMODATE DIFFERENTIAL LONGITUDINAL AND TRANSVERSE EXPANSION AND CONTRACTION WITH RESPECT TO THE FRAME WORK. THE FRAMEWORK INCLUDES PARALLEL SUPPORT RAILS THAT COOPERATE WITH A PERIPHERAL PLANAR AREA OR PORTION AND OVERHANGING LIPS AT THE FRONT AND BACK FOR NONSTRESSING SUPPORT OF THE SEAT MODULES. EMBOSSMENTS ON THE LIPS PROVIDE TRANSVERSE SNUGNESS. LATERALLY EXTENDING FINISH STRIPS COVER THE JOINT BETWEEN THE SEATS AND HOLD DOWN THE EDGES, AND ALSO COVER THE EMBOSSEMENTS. A SLOT IS PROVIDED ALONG EACH RAIL FOR RECEIVING A BOLT, A BARREL NUT BEING DRIVEN ON THE BOLT TO FASTEN THE SEAT MODULES IN POSITION WITH ONLY TOP DRIVE BEING APPLIED. THE BOLT HEAD IS SUFFICIENTLY NARROW TO DROP BETWEEN THE SHOULDERS OF THE SLOT WHEREUPON THE SIDES OF THE SLOT LIMIT ROTATION OF THE BOLT TO AN OBLIQUE ANGLE AND INSURE ENGAGEMENT OF THE HEAD WITH SAID SHOULDERS IN FASTENING RELATIONSHIP. THE NUT INCLUDES A CULINDRICAL BODY HAVING A LOWER FACE FOR ENGAGEMENT WITH THE FRAMEWORK IN FRICTIONAL LOCKING RELATIONSHIP-, THE BODY BEING SUBSTANTIALLY THE SAME LENGTH AD THE THICKNESS OF THE PANELS (SUCH AS THE FINISH STRIP AND SEAT OR TRANSPORT TRAILER SKIN) TO OBVIATE COMPRESSION STRESSES WITHIN SAID PANELS AND ALLOW A FLOATING INTERCONNECTION FOR DIFFERENTIAL EXPANSION AND CONTRACTION AND MECHANICAL VIBRATION.

Description

NOV. 7, 1972 I TIPTQN ETAL 3,702,204

MODULAR SEATING ASSEMBLY Filed Sept. 15, 1970 I5 Sheets-Sheet l NOV. 7, 1972 TIPTQN ETAL 3,702,204

MODULAR SEATING ASSEMBLY Filed Sept. 15, 1970 5 Sheets-Sheet 2 I 52 g QVQLgEzEScHL/JZ iffO/ZA/f)? Nov. 7, 1972 M. E. TIPTON EIAL 3,702,204

MODULAR SEATING ASSEMBLY Filed Sept. 15, 1970 3 Sheets-Sheet 5 p [/6622 )BOB if MAX E. 77pm M1 M67? 6 5mm 72 fllllllmmlllllll luvo I vibration.

United States Patent 3,702,204 MODULAR SEATING ASSEMBLY Max E. Tipton, Easton, and Wilmer R. Schultz, Emmaus, Pa., assignors t0 Wilmer R. Schultz, Emmaus, Pa. Filed Sept. 15, 1970, Ser. No. 72,416 Int. Cl. A47c 1/ 12 US. Cl. 297248 36 Claims ABSTRACT OF THE DISCLOSURE Modular seats molded of plastic material are securely supported on an elongated framework by fasteners extending between and abutting the adjacent side edges of the seats While serving to accommodate differential longitudinal and transverse expansion and contraction with respect to the framework. The framework includes parallel support rails that cooperate with a peripheral planar area or portion and overhanging lips at the front and back for nonstressing support of the seat modules. Embossments on the lips provide transverse snugness. Laterally extending finish strips cover the joint between the seats and hold down the edges, and also cover the embossments. A slot is provided along each rail for receiving a bolt; a barrel nut being driven on the bolt to fasten the seat modules in position with only top drive being applied. The bolt head is sufiiciently narrow to drop between the shoulders of the slot whereupon the sides of the slot limit rotation of the bolt to an oblique angle and insure engagement of the head with said shoulders in fastening relationship. The nut includes a cylindrical body having a lower face for engagement with the framework in frictional locking relationship; the body being substantially the same length as the thickness of the panels (such as the finish strip and seat or transport trailer skin) to obviate compression stresses within said panels and allow a floating interconnection for differential expansion and contraction and mechanical The present invention relates to modular seating and, more particularly, to an improved combination of modular seats and supporting framework for installation in a stadium or the like.

BACKGROUND OF THE INVENTION Stadium or bleacher seating has in the past been made in the form of benches or chairs utilizing wooden planks or slats. Wood is an ideal material in that it has a relatively low coefficient of thermal expansion and contraction and high resiliency, as well as a low heat transfer coefficient. Thus, it is ideal for preventing damage resulting from differential expansion and contraction with respect to its base and from vibrations, and in providing a temperate seat on which to sit. However, as the worlds supply of wood has become more in demand for other uses, such as furniture, paper, etc., and thus has risen in price, it has become impractical to continue fabricating large numbers of stadium seats from wood. Also, Wooden components have always suffered the inherent disadvantage of eventually being subject to deterioration from weathering and the attendant high cost of maintenance, including annual painting.

To fill this gap, the modular seating concept wherein seats of unitary molded plastic material are assembled in juxtaposition on a support has appeared on the scene. The concept offers outstanding potential in terms of initial low cost since the seats are formed of thin, vacuum molded plastic, and promises even greater savings in terms of being maintenance-free for the life of the stadium. Another advantage of the modular seats is outstanding spectator or user appeal in that they may be fully contoured to fit the human anatomy, they provide insulation "Ice from extreme heat and cold, and they are permanently colored for aesthetic purposes and stadium section identification. One recent patent, illustrating this broad concept and owned by the assignee of the present invention, is the patent to Motter 3,466,087, issued Sept. 9, 1969.

Historically, this concept of modular stadium seating has been distressed by the need for basic development and refinements in terms of translating the concept into a simplified structure or assembly that is permanent and OBJECTIVES OF THE INVENTION Accordingly, it is one object of the present invention to provide an improved seat module and modular seating assembly for stadiums wherein modular seats are securely mounted (without loose parts) in juxtaposition on a supporting framework so as to allow differential expansion and contraction, while at the same time achieving a simplified structure and lowest cost per unit.

It is another objective of the present invention to provide a seat module of plastic material that is not subject to stresses tending to weaken and fracture the same, and adapted to fit on the supporting framework in juxtaposition with like modules in a snug fashion.

It is another object of the present invention to provide a support framework and fastener means to which the seat modules may be attached in a highly expedient manner and with the use of only top drive tools to greatly enhance the efficiency of the installation.

It is still another object of the present invention to provide an improved fastener for cooperating with the support framework to fix the seating modules or other panels in position without causing weakening stresses therein.

SUMMARY OF THE INVENTION Briefly, the present invention provides contoured seat modules having several features particularly adapting the same for securing to an elongated framework in juxtaposition with like modules in a snug fashion and so as to prevent stresses in the modules due to ambient thermal variations and vibrations. The seat module is made of a unitary sheet of plastic material, which material may be brightly colored to enhance the attractiveness of the stadium and to conveniently provide color coding for different sections of the stadium. The central portion is raised and contoured to fit the anatomy of the spectator or user. An outer peripheral planar portion provides an extended area across the full width of the front and back for support of the module on the framework which prevents the weight of the spectator from causing deleterious stresses in the plastic material that would, like the thermal variations and vibrations, eventually lead to fracture and cracking. Embossments are formed adjacent the sides of the seat modules on the overhanging lips that insure the seat of having a snug fit on the framework in the transverse direction with respect to said framework; the center expanse of the lips being free to move in or out to accommodate differential expansion and contraction between the module and the framework in the same transverse direction.

The framework preferably comprises a pair of parallel runner rails, the top surfaces of which engage the planar supporting surface of the seat modules along the front and rear. Also provided are cantilever channels formed in the rails which are engaged by the front and rear depending lips for transverse positioning of the modules. Slots are formed along the length of the rails for adjustably receiving a threaded bolt which, with a barrel nut, forms the fastener means holding the seat modules in position. The nut includes a cylindrical body having a length equal to the thickness of the seat and finish strip that conceals the joint between two adjacent seat modules. The lower face of the cylindrical body is adapted to frictionally lock into engagement with the opposite or upper side of the retaining shoulders of the slot that holds the head of the bolt against upward movement; the bold head being sufiiciently narrow to drop into the slot at any position along the length for ease of installation and then turn to an oblique angle as limited by the sides of the slot in fastening relationship with the shoulders.

The framework includes a cross bar to connect the rails; an inverted U clamp engaging a groove on the rails to lock the same in position for easy on-site attachment of these parts. Either a vertical riser support or tread support may be attached to the cross bar for support of the assembly on the usual stepped concrete stadium base.

The use of the nonstressing fastener and cooperating rail mount of the present invention may be translated into other fields, such as the field of fabrication of trailer truck skin. In this instance, the rails form the framework for the trailer body and the outer panels are attached in the same manner as the seat modules and/or the finish strip means with the same resultant self-locking feature of the fasteners. The prevention of stressing and cracking of the panels due to road vibrations and expansion or contraction due to change in thermal conditions represents a significant advance in these other fields.

Still other objects and advantages of the present invention will become readily apparent to those skilled in this art from the following detailed description, wherein we have shown and described only the preferred embodiments of the invention, simply by way of illustration of the best modes contemplated by us of carrying out our invention. As will be realized, the invention is capable of other and different embodiments, and its several details are capable of modification in various obvious respects, all without departing from the invention. Accordingly, the drawings and description are to be regarded as illustrative in nature, and not as restrictive.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perpsective view of a preferred embodiment of a modular seating assembly constructed in accordance with the principles of the present invention with parts for one module being shown in exploded form for clarity;

FIG. 2 is a top view of the modular seating assembly of FIG. 1 illustrating the interconnected seat modules and lateral finish strips therebetween;

FIG. 3 is a front view of the modular seating assembly of FIG. 1 with a riser type mount;

FIG. 3a is a front view of the modular seating assembly of FIG. 1 with a tread type mount;

FIG. 4 is a cross-sectional view taken along line 44 of FIG. 2 illustrating the fastener means in operative position;

FIG. 5 is an enlarged view showing the bolt and barrel nut of the preferred form of fastener;

FIG. 6 is a cross-sectional view taken along line 6-6 of FIG. 4 showing the locking action of the bolt head and the retaining slot and the barrel nut;

FIG. 7 is an enlarged and emphasized view of the floating action of the seat modules abutting the fasteners at the joints;

FIG. 8 is a cross-sectional view showing the application of the fastener of the present invention to trailer fabrication field utilizing corrugated skin; and

FIG. 8a is a cross-sectional view showing the application of the fastener of the present invention to trailer fabrication field except utilizing planar skin.

4 DETAILED DESCRIPTION OF THE INVENTION For a more complete description of a preferred embodiment of the stadium seating assembly and the advantages attendant thereto, reference is now made to FIGS. 1-3 of the drawings wherein is shown a stadium seating assembly, generally designated by the reference numeral 10, and including a framework 11 fabricated of suitable parts of metal, such as aluminum, and a plurality of seat modules 12, formed of any suitable high strength plastic material, such as high density polyethylene. As illustrated, the seat modules 12 are formed of sheet material with a raised central portion 13 having a contour suited for comfortably accommodating the users anatomy. For excellent low-cost production, the preferred embodiment is made by vacuum molding in a single-step operation; although it is to be understood that other methods of fabrication can be used if desired.

The framework 11 comprises a pair of

parallel rails

15, 16, the top, planar surfaces of which serve to support the seat modules 12 along the front and rear in a normal, horizontal position. Cross bar 17 is provided to interconnect the

rails

15, 16 and to support the same from vertical riser support member 18. The cross section of the cross bar 17 and the riser member 18 can be of any suitable configuration to give the requisite strength to the framework 11 and for purposes of illustration of the preferred embodiment the cross bar 17 is shown as a T section and the riser member is shown as an angle (see FIGS. 1 and 3). The riser member 18 may be suitably mounted on riser face 19 of a conventional stepped stadium base as shown in FIGS. 1 and 3, or in the alternative, the framework 11 may be supported from the tread 20, as shown by tread support member 18a in FIG. 3a. As illustrated in these figures, the attachment of the riser and

tread members

18, 18a may be by suitable stud and bolt

combinations

21, 21a, respectively, and the interconnection of the cross bar 17 to the riser and

tread members

18, 18a may be by bolt and nut combination 22 (see FIG. 3); although it is to be understood that other conventional types of fastening might be used at these points if desired without departing from the broad prin ciples of the invention.

To now consider the important aspects of the improved seat module 12 constructed in accordance with the present invention, reference is made back to FIG. 1, wherein it can be seen that the raised, contoured portion 13 is defined by an outer, vertical wall 25 extending along the front and two sides and curving around the back at both sides. In the front is a ridge 26 dimensioned to fit between the legs of the user in a seated position, which ridge tapers to the rear toward the dished-out section and to the front to provide a surface suitable for marking of the desired seat number. Extending peripherally around the outside wall 25 is a planar portion 27 that provides the seat with a level undersurface area to mate with the top plannar face of the front and back rails 15, 16 in supporting relationship therewith. Because the supporting engagement is thus spread out over the peripheral planar area 27 along the entire front and back, stresses in the plastic material are avoided and the serviceability of the modules 12 is greatly extended. Also, increased rigidity of the modular seat 12 results from the raised central portion 13 as defined by the outer wall 25, thereby giving a seat superior in strength and support efliciency to further prevent stresses and present a more serviceable product. It will be noted that the center rear of the contoured portion 13 is coextensive with the planar area 27 so that moisture is not retained on the module 12.

Along the front of the module 12 and along the rear are provided overhanging lips 30, 31 (see FIGS. 1 and 4) fixing said modules 12 on the framework 11 in the direction transverse thereto. These lips are coextensive with and engage

channels

32, 33, which face outwardly from and give improved transverse strength to the

rails

15, 16.

By making these

lips

30, 31 coextensive with the

channel members

32, 33, the only exposed face of the rail (the lower portion) is displaced rearwardly to prevent contact of the spectators legs in a normal seated position.

It is well known that plastic has a higher coeflicient of thermal expansion and contraction than metal, and the assembly 10 of the present invention has thus been provided with several unique features to permit shifting of the parts relative to each other so as to prevent the formation of deleterious stresses in the plastic while maintaining a snug fit at all temperatures.

First, adjacent the edges of the seat module 12 and extending vertically across the width of the overhanging

lips

30, 31 are provided

embossments

35, 36 to insure spacing of the

lips

30, 31 away from the framework 11 under all ambient thermal conditions. In other words, as shown in FIGS. 1 and 4, the convex protrusion on the underside surface of the module 12 spaces the

lips

30, 31 away from the

channels

32, 33. This allows the central expanse or major length of the lips to freely move in and out with respect to the

channels

32, 33 in order to accommodate differential expansion and contraction between the modules 12 and the framework 11. That is, transverse contraction of the module 12 with respect to the framework 11 is accommodated since only the

embossments

35, 36 are in engagement with the

channels

32, 33 and therefore resist the pulling in whereby these lateral edges of the

lips

30, 31 are free to twist and bow outwardly without providing significant stresses to the plastic. On the other hand, upon expansion of the module 12, the

embossments

35, 36 maintain only light engagement at the lateral edges as the center expanse of the

lips

30, 31 tends to move further away. Accordingly, excessive stresses in the module 12 are prevented, while at the same time the module 12 is retained in a sung condition on the

rails

15, 16.

The

embossments

35, 36 engage the outwardly extending face of the

channels

32, 33 along a substantial line contact so that slack between the seat modules 12 and the framework 11 is more effectively prevented. Further, the

embossments

35, 36 have sufficient frictional engagement with the

channels

32, 33 to resist any tendency toward lateral shifting of the modules 12 along the

rails

15, 16.

According to the second important feature of the present invention concerning accommodation of differential expansion and contraction, the juxtaposed modules 12 are fixed in position by fasteners F including an upstanding bolt 40 and barrel nut 41, which fastener extends between and abuts the sides of the modules 12 and thereby allows a modified floating interconnection therebetween as will presently be seen. Each bolt 40 cooperates with the rails in such manner that a tool for activating the fastener is required to be employed only from above. This is best shown in FIGS. 5 and 6 wherein it can be seen that the bolt 40 includes an elongated head 42 that is adapted for positioning in a slot 43 along each of the

rails

15, 16. As illustrated, the slot has opposed retaining

shoulders

44, 45 along top thereof for holding the head of the bolt against upward movement. However, as will be apparent, the bolt is permitted adjustable horizontal movement with respect to the framework 11 along its entire length by simply grasping the upstanding threaded portion and moving the same as desired. When the selected position of adjustment is reached, the barrel nut 41 is driven onto the bolt 40, and due to the frictional forces between the corresponding threads, the head 42 is initially rotated to an oblique angle so that the ends thereof are automatically in cooperative or locking relationship with the

shoulders

44, 45. The side walls of the slot 43 limit the movement of the bolt head 42 to thereby provide the final locking position of the head 42 with respect to the

shoulders

44, 45.

The heads 42 are sufliciently narrow to pass between the

shoulders

44, 45 when extending along the longitudinal axis, as shown in the full line position of FIG. 6.

This allows the installer of the assembly 10 to simply drop the bolts 40 into the approximate location along the length of the rails after each module 12 is placed thereon, and then make the final adjustment by sliding along the slot. This obviates having to preassemble the fasteners on the rail by inserting them through the end opening and sliding over what could be a considerable distance to the final required location.

To accommodate differential expansion and contraction between the framework 11 and the modules 12 in the longitudinal direction with respect to the framework, the fasteners F extend between the adjacent edges of the modules 12 to form an open joint 50 (see dotted line showing in FIG. 2, and see FIG. 7). In the embodiment shown, there are thus two isolated bearing surfaces 51, 52 defined at each fastener F and the abutted edges of the area 27 on the modules 12 (see FIG. 7). Since the force of expansion (at higher temperatures) in the longitudinal direction (see arrows a a is thus concentrated at only two points, a slight deformation (exaggerated in FIG. 7 for illustrative purposes) of the edges of the plastic material at these two spaced locations may take place. It has been discovered that when utilizing a high density plastic material of the polyethylene resin type, the edges have sufiicient resiliency to so deform locally without causing stresses in the body of the module 12, and then the edges return to their normal configuration over an infinite number of cycles without significant weakening thereof. Differential contraction in the longitudinal direction (due to cooler ambient temperatures) tends to widen the joint 50 and similarly no stresses are placed on the body of the module 12. Expansion and contraction in the transverse direction, that is, in the direction of the arrow (1 (FIG. 7) is accommodated by simply sliding of the edges of the modules 12 with respect to the fastener F.

Assuming a median ambient temperature in the neigh- Iborhood of 70 F., it has been found that the modules 12 are capable of being installed in abutting relationship with the fasteners F as mentioned above, which greatly assists in gaining a uniform, snug fit of the modules 12 on the framework 11. With this structure, no measurements or sub ective judgments are needed to be employed by the installer to insure the proper installation.

Thus, it can be seen that the juxtaposed modules 12 are mounted in a positive and secure manner, but yet are capable of modified floating movement at the interconnections by virtue of the required expansion and contractron in both the longitudinal and transverse direction with respect to the framework 11 to prevent deleterious stresses. The contacts made by the

embossments

35,, 36 and the fasteners F insure this capability while at the same time always insuring a snug fit between the parts.

The fastener means F are securely locked in position in an automatic fashion as they are driven into final position. That is, lower face 55 of the barrel nut 41 is provided with a frictional surface that is adapted to cooperate with the upper surface of the

rails

15, 16, and in particular, the side of retaining

shoulders

44, 45 opposite from the head 42 of the bolt 40, as shown in FIG. 4. It should be noted that the nut 41 and the head 42 thus act on substantially directly opposite sides of the

shoulders

44, 45 with equal and opposite reactions and thus no force tendmg to strip out the

shoulders

44, 45 is experienced due to the tightening action.

The torque with which the barrel nut 41 is driven into final position is controlled by adjustment of the power tool being used. The preferable adjustment is for sufiiciently high torque to cause the lower face 55 to form a partial cold weld; that is, a partial fusing together of the adjacent molecules in the contact area between the lower face 55 and the upper face of the

shoulders

44, 45 due to the frictional heat generated by the galling action (see FIG. 6). The barrel nut 41, like the

rails

15, 16, is fabricated of an aluminum alloy so as to be relatively soft and thus capable of readily forming such a weld.

The lower face 55 of the barrel nut 41 may, if desirable or necessary, be provided with a plurality of rearwardly extending teeth to form a serrated surface as shown in FIG. 5. Thus, when the nut 41 is driven down into final position, the knife edges of the serrations more completely resist any tendency for reverse rotation by biting into the metal face of the

rails

15, 16.

A lateral finish strip 60 is mounted between adjacent seat modules 12 by the barrel nuts 41, as shown in FIGS. l-4. The

apertures

61, 62 through which the nuts 41 pass are slightly oversized to accommodate the required degree of expansion and contraction of this part. The head of the nut 41 is adapted to frictionally engage the upper surface of the finish strip 60 so as to firmly hold the same down and transfer a downward holding force in turn to the edges of the seat modules 12 aloing the surface of the planar area 27. However, the strip 60 and the planar portion 27 of the seat module 12 are not subjected to compressive stresses as in prior arrangements by virture of the feature of making the cylindrical body of the nut 41 a length substantially equal to the combined thicknesses of these parts. The making of the body approximately five thousandths (.005) of an inch shorter than the combined widths has been found to give the most favorable result of providing a uniform clamping force for the interconnection. With this arrangement, minimum stress is experienced in the plastic and cracks and eventual failure, like- 1y to be experienced with prior arrangements, are avoided.

The finish strip performs the function of concealing the open joint 50 between the juxtaposed modules 12 (see FIG. 2). Furthermore, the

embossments

35, 36 are positioned at the edges of the

lips

30, 31 and thus the finish strip 60 will also cover these elements. End finish strips 65 are provided with end wall 66 in order to conceal the framework 11 at the end of a row of seats.

The

rails

15, 16 have lower and upper inwardly directed flanges 70, 71 between which the ends of the cross bar 17 are fitted for mounting stability. In order to firmly attach the rails to the cross bar, a U-shaped clamp 72 positioned in an inverted position is mounted spanning the connection between the upper flange 71 of each rail ad the upper surface of the cross bar 17. The leg of the clamp 72 cooperating with the flange 71 may be fitted in a longitudinal groove 73 formed in said flange 71 along the entire length thereof. The cooperation between the leg and the groove 73 securely locks the

rails

15, 16 in position upon tightening of the self-tapping screw fastener 74 engaging a predrilled hole in the cross bar 17.

From the foregoing, it can be realized that a modular seating assembly has been provided that is practical for low cost, mass production and easy installation. The modular seat 12 is provided with a planar peripheral area 27 that rests on a corresponding fiat surface of the framework 11 so as to provide a secure support relationship. The fastener means F comprising the bolt 40 (adjustable along the

rails

15, 16 in a slot 43), and the barrel nut 41 locks in position to hold the modules 12 on the framework 11. The body of the nut is substantially the same length as the thickness of the finish strip 60 and seat edge so that substantial compressive stresses in the plastic are avoided.

The arrangement of the fasteners F in combination with a mounting framework is contemplated by us as having certain utility out of the seating field but still coming within the bounds of the present inventive concept. For example, as shown in FIGS. 8 and 8a, the mounting of corrugated panel 60a or flat panel 60b on the rail for forming an enclosure has certain very important advantages.

To further explain, in the environment of mounting the skin of a transport trailer body, it is necessary for some form of fastener to be used to fasten the panels in place. In the past, rivets have been accepted as the standard. These rivets rigidly clamp the skin to the support framework and place the skin panels under substantial compressive stress in the areas around the apertures for the fasteners. The proposal of our inventive concept is to utilize the fasteners F, the oversized apertures 61 and the rail 15 in combination to mount either the corrugated panel 60a with a nominal thickness t or a planar panel 60b with a thickness of material t in the same manner that is employed for the finish strip 60 and the seat module 12 described above. With this arrangement, expansion and contraction are allowed in the panels and flexure of the sides due to mechanical vibration is also accommodated so that stresses are not present and cracking is prevented. The panels 60a, 60b in the trailer environment are commonly made of aluminum sheets and the prevention of stresses allows the use of thinner gauge material for a substantial savings in cost while maintaining the integrity and watertightness of the trailer body.

In this disclosure, there are shown and described only the preferred embodiments of the invention, but, as aforementioned, it is to be understood that the invention is capable of various changes or modifications within the scope of the inventive concept as expressed by the accompanying claims.

We claim:

1. A modular seating assembly for stadiums or the like comprising an elongated support framework presenting a substantially fiat horizontal plane, a plurality of separate seat modules mounted in juxtaposition in a row on said framework, said seat modules having laterally extending substantially fiat planar portions cooperating with the horizontal plane of said framework for support and defining side edges, and fastener means outside said planar portions extending between and abutting the side edges of said modules and cooperating with said framework for fixing said modules in position while allowing differential expansion and contraction of said framework and seat modules and allowing movement of both juxtaposed edges in a plane toward each other during such expansion and contraction, said fastener means extending in a direction across said row substantially less than the full width of said row, the movement of said side edges toward said fastener means being accommodated by localized deformation of said edges at said fastener means.

2. The assembly of claim 1 wherein is further provided means for activating said fastener means by employing a tool only from above, whereby installation is expedited.

3. The assembly of claim 1 wherein said fastener means includes a first upstanding threaded member extending between said modules and a corresponding second threaded member for driving between said modules on the first threaded member, and locking means including a lower frictional surface on said second member en gaging the upper face of said framework upon being driven into final position.

4. The assembly of claim 3 wherein said first threaded member includes a bolt, a slot extending longitudinally along said framework, opposed shoulders along the top of said slot holding the head of said bolt against upward movement but allowing manual adjustable horizontal movement with respect to said framework by grasping the upstanding threaded portion, said second member including a corresponding nut, said lower frictional surface being the lower face of said nut, said lower face engaging the opposite side of said shoulders from said bolt head for locking.

5. The assembly of claim 4 wherein said lower face is provided with reversely directed serrated teeth for biting into the framework to form said locking means.

6. The assembly of claim 4 wherein said bolt head is sufficiently narrow to fit between said shoulders for installation into said slot, and said head being free to turn to an oblique angle with respect to said slot for engagement of the side walls thereof to provide locking engagement with said shoulders.

7. The assembly of claim 4 wherein the side edges of adjacent modules are spaced apart by said fastener means so as to form an open joint therebetween, and wherein is further provided lateral finish strip means between said modules to hold down said edges and to conceal the joint, said nut includes a cylindrical body substantially equal in length to the combined thickness of the edge of said seat module and said finish strip, whereby stresses are prevented therein.

8. The assembly of claim 1 wherein the side edges of adjacent modules are spaced apart by said fastener means so as to form an open joint therebetween, and wherein is further provided lateral finish strip means between said modules to hold down said edges and to conceal the joint.

9. A modular seating assembly for stadiums or the like comprising an elongated support framework including a pair of parallel rails, a plurality of separate seat modules mounted in juxtaposition in a row on said rails, said rails extending in the direction of the row, one rail extending along the front and another along the rear of said modules, and first and second fastener means cooperating independently of each other with a respective one of said rails for fixing said modules in position, attachment means extending substantially along the full length of said rails, said fastener means being capable of adjustable movement along said attachment means of said rails in the direction of said row, said fastener means including a first upstanding threaded member and a corresponding second threaded member for driving from above on the first threaded member and abutting the side edges of said seat modules, and locking means on said fastener means including a lower friitional surface on said second member engaging the upper face of said framework upon being driven into final position.

10. The assembly of claim 9 wherein said first threaded member includes a bolt, said attachment means includes a slot extending longitudinally along said rails, opposed shoulders along the top of said slot holding the head of said bolt against upward movement but allowing manual adjustable horizontal movement with respect to said rails by grasping the upstanding threaded portion, said second member including a corresponding nut, said lower frictional surface being the lower face of said nut, said lower face engaging the opposite side of said shoulders from said bolt head for locking.

11. The assembly of claim 10 wherein said bolt and nut extend between adjacent seat modules and abut the side edges of said modules, said nut having a cylindrical body for engagement with said edges.

12. The assembly of claim 11 wherein the side edges of adjacent modules are spaced apart by said cylindrical body so as to form open joint therebetween, and wherein is further provided lateral finish strip means between said modules to hold down said edges and to conceal the joint.

13. The assembly of claim 9 wherein said seat modules include a raised central seat portion and overhanging front and rear lip portions engaging said rails to resist transverse movement of said modules with respect to said framework and to insulate the user from said framework.

14. The assembly of claim 13 wherein said rails include outwardly facing cantilevered channels with the open portion facing toward the inside, said lip portion corresponding to the width of said channel.

15. The assembly of claim 13 wherein said lip portions include inwardly directed protrusions on the underneath side thereof and adjacent the side edges of said seat module, the center portion of the lip portions extending substantially the full distance between said protrusions, and said center portion being spaced from and said protrusions being in engagement with the outer faces of said rails, whereby to provide a snug transverse fit of said modules on said rails.

16. The assembly of claim 15 wherein said protrusions are formed by relatively narrow embossments compared to the width of the seat and extending substantially perpendicular thereto along said lip portions, the convex side being in engagement with said outer faces.

17. The assembly of claim 16 wherein is provided a lateral finish strip means between adjacent modules to hold down said edges and to conceal the joint therebetween, said finish strip means being on the concave side of said embossments and having suflicient width to also completely conceal said embossments.

18. The assembly of claim 9 wherein said parallel rails are connected by a cross bar and clamp means for securing said cross bar to said rails.

19. The assembly of claim 18 wherein said clamp means includes an inverted U-shaped member, a groove formed lengthwise of said rail for receiving one leg of said U- shaped member, the other leg engaging said cross bar, and means attached to said cross bar for drawing said U- shaped member down into locking frictional engagement with said rail and said cross bar to secure said rail in position.

I 20. The assembly of claim 19 wherein a riser support is attached to said cross bar for positioning said assembly in situ to the riser of a stepped base of the stadium.

21. The assembly of claim 19 wherein a tread support is attached to said cross bar for positioning said assembly in situ to the tread of a stepped base of the stadium.

22. A seat module for permanent attachment in continuous juxtaposition with like seats to a supportin elongated framework for stadiums or the like comprising a unitary sheet of molded plastic material, said seat module comprising front and back downwardly extending lips for overhanging engagement with the corresponding front and back of said framework for transverse positioning with respect to said framework, a raised central seat portion on which the user can sit, a substantially peripheral horizontal planar portion providing a fiat mounting area for engagement with the top of said framework, said planar portion extending along substantially the full length of the front and back of said module and being sufficiently strong to support the weight on said raised seat portion, whereby said seat may be secured and held in position on said framework with a minimum amount of stress.

23. The seat of claim 22 wherein is provided protrusion means on the underneath side of said lips directed toward and for positive engagement with said framework to cause a snug lateral fit, the central portion of said lips being spaced from said framework to allow expansion and contraction.

24. The seat of claim 23 wherein said protrusion means is formed by embossments in said overhanging lips, the convex side of said embossments providing substantial line contact between said seat and said framework.

25. The module seating assembly of claim 1 wherein said seat module includes front and back downwardly extending lip portions, a raised contoured central seat portion on which the user can sit and protrusions on the underside of said lips inwardly directed toward and for positive engagement with the outwardly directed faces of said framework to insure a snug fit between said seat and said framework, the central portion of said lips extending substantially the full distance between said protrusions, and said center portion being spaced from said framework to allow expansion and contraction.

26. The seat of claim 25 wherein each protrusion comprises an embossment formed in said plastic material, the convex side of said embossment being on the underneath side of said seat for engagement with said framework, said embossment being elongated to provide substantial line contact with said framework.

27. The seat of claim 25 wherein the peripheral portion of said seat includes horizontal front and back portions that are planar to provide a substantial fiat mounting area with respect to said framework.

28. The seat of claim 25 wherein said protrusion means is adjacent the side edges of said seat for ease of concealment, and to allow inward and outward movement of the center expanse of the lip portions.

29. A cover panel and framework assembly comprising elongated rails forming at least a portion of said framework, a first threaded member in the form of a bolt, means for attaching said first threaded member to said rail, said attaching means including an elongated slot extending along the length of said rail, opposed shoulders along the top of said slot for holding the head of said bolt against outward movement but allowing manual adjustable longitudinal movement with respect to said rail by grasping the projecting threaded portion, a second corresponding threaded member for driving on said first threaded member, said second threaded member including a cylindrical body forming a barrel nut, compressible panel means being an exterior covering and held in position by said second threaded member, an exposed head accessible from the panel side for driving of said second member, said panel means having a thickness substantially equal to the length of said cylindrical body, a frictional surface being formed on the lower face of said body, and means on said rail for cooperating with said surface to limit the downward driving movement and frictionally lock said second threaded member in position and firmly grip said rail, whereby positive locking of said panel in position is obtained without compressive stress being transferred to said panel.

30. The assembly of claim 27 wherein said second threaded member extends through apertures formed in said panel, said apertures being oversized in all directions to accommodate differential expansion and contraction of said panel and framework.

31. The assembly of claim 30 wherein is further provided a separate second panel at least partially coextensive with said first panel, the combined thicknesses of said panels being substantially equal to the length of said body.

32. The assembly of claim 31 wherein said second panel has an edge abutting said body, said first panel overlying said edge to conceal the same.

33. The assembly of claim 29 wherein the head of said 12 bolt is sufiiciently narrow to pass between said opposed shoulders, the sides of said slot serving to limit the rotation of said bolt upon application of driving force to said nut whereby said head of said bolt assumes an oblique angle for engagement with said shoulders in fastening relationship.

34. The assembly of claim 9 wherein is further provided means for activating said fastener means by employing a tool only from above, whereby installation is expedited.

35. The assembly of claim 9 wherein said first and second fastener means extend between two adjacent modules and abut the side edges thereof, said fastener means cooperating with said framework for fixing said modules by abutment in position while allowing differential expansion and contraction of said framework and seat modules and allowing movement of both juxtaposed edges in a plane toward each other during such expansion and contraction, the movement of said side edges toward said fastener means being accommodated by deformation of said edges.

36. The assembly of claim 27 wherein said panel means is disposed substantially horizontally and means for activating said threaded members by employing a tool only from above, whereby installation is expedited.

References Cited UNITED STATES PATENTS 1,998,936 4/1935 Luce -4 2,302,969 11/1942 McMahan 297-443 3,006,689 10/1961 Eppink 297-DIG. 2 3,042,973 7/1962 Earnes et al. 287-18936 F 3,371,956 3/1968 Jordan et al. 297-248 3,397,011 8/1968 Sklaar 297-219 3,466,087 9/1969 Motter 297-232 3,482,874 12/ 1969 Henebry et a1 297-248 3,494,466 2/ 1970 Schaefer et al. 297-248 3,531,157 9/1970 Duckett et a1. 297-248 3,554,142 1/1971 Sorenson et al. 248-235 FRANCIS K. ZUGEL, Primary Examiner US. Cl. X.R. 297-452, DIG. 2