US 3729877 A
A folding truss is disclosed wherein the main beam member in a fully opened condition is arranged in a straight line and in a folded condition is disposed to be compacted to lay in an accordian style. The members providing the straight beam are hinged so as to mate and engage each other in an end-to-end arrangement when the beam is fully opened. A series of connected support arms are pivotally mounted on pins secured to the mid-portions of the main beam members. The connected support arms are pivotally connected at their ends to each other and when the main beam members are in the straight line fully opened condition the support members, which are longer than the main beam members, are disposed in a zig-zag pattern which may be about a 30 to 40 DEG angle or slope to the axis of the main straight beam.
Description (OCR text may contain errors)
United States Patent 1 [1 1 3,729,877 Hall 1451 May 1, 1973 1 FOLDING TRUSS Primary ExqminerFrank L. Abbott  Inventor: Raymond L. Hall, 19 Hamilton Assistant Examiner-Leslie Bran Court pp y NJ. 0798] Attorney-Ralph R. Roberts  Filed: Sept. 29, 1971 57 ABSTRACT Appl. No.: 184,758
A folding truss is disclosed wherein the main beam member in a fully opened condition is arranged in a straight line and in a folded condition is disposed to be compacted to lay in an accordian style. The members providing the straight beam are hinged so as to mate and engage each other in an end-to-end arrangement when the beam is fully opened. A series of connected support arms are pivotally mounted on pins secured to the mid-portions of the main beam members. The connected support arms are pivotally connected at their ends to-each other and when the main beam members are in the straight line fully opened condition the support members, which are longer than the main beam members, are disposed in a zig-zag pattern which may be about a 30 to 40 angle or slope to the axis of the main straight beam.
7 Claims, 3 Drawing Figures Patented May 1, 1973 INVENTOR. RAYMOND L HA LL AGENT FOLDING TRUSS BACKGROUND OF THE INVENTION truss-adjustable; the subclass identified as truss-exl0 pansion device; the subclass identified as girder and the subclass identified as lazy tongs."
Pertinent art may also be found in the general class of Static Structures" and the subclass under openwork" which subclass is further identified as components adjustably or collapsibly connected.
2. Description of the Prior Art In the construction of covers and extensible beams it is often highly desirable that straight line supports or the straight compression beam or straight tension member have folding properties which permit reasonably compact storage for transportation and for covering and uncovering determined areas. For example, where two beams are to provide a support for a surface such as a walk-way or as'a support for a conveyor, which units after use are folded for storage in a truck or the like, it is desirable that the straight member be supported at a minimum number of points while the tension member or support is able to be folded into the minimum spacefor storage. In particular, covers for swimming pools or other open areas usually require a side retaining means in order to be retained in the desired condition. However, during substantial portions of use they are to be folded so that the general area may be exposed to the sun and the natural environment, hence, the storage space for the cover should be as little as possible. In the extended condition when in or ready for use such covers may be subject to loads of snow and be subjected to rain and wind which require that the strength member have a determined capacity. Where the strength member is to act as a support for a bridge, a conveyor or like support surface which is to be foldable, it is also desirable that the straight compressive beam have sufficient strength to be supported on two selected points. These two or more support points may be any convenient place along the truss or beam which would be normally used with a straight beam.
Sissor-like members which expand and contract in a straight line in accordance with accordian-pleated principles have equal length legs and when they are expanded to a determined length they do not have the rigidity of a single member beam. The present invention provides a beam-like member which may be used as either a tension or a compression member in that in its fully opened or extended condition one of the truss members is a straight member. The other truss members are support arms which, like theconventional truss, lay in diagonal patterns in relation to the main beam member. The truss of this invention resembles the usual sissor-like construction only during the folded or partially erect condition.
SUMMARY OF THE INVENTION This invention may be summarized at least in part by references to its objects. It is an object of this invention to provide and it does provide, a folding truss or beam which in its fully opened condition has one member as a straight member while the supporting members are arranged in a connected zigzag manner.
It is a further object of this invention to provide and it does provide, a folding truss or beam wherein as a tension or compression member one of the connected series of members is caused to be brought to a straight condition. In a tension capacity the straight members may limit the expansion of the accordian-type supporting members.
The folding truss or beam of this invention may be used or arranged in like pairs of miltiples thereof sothat in its fully opened condition one of the series of connected members becomes a straight compression or tension member with a series of pivotally connected supporting member portions arranged in a zig-zag manner to support and control the attitude of the straight line beam portion. This folding beam portion is hinged at the connected ends. When the straight beam portion is brought to its folded condition it lays or is disposed in an accordian manner. In a straight line fully expanded condition the straight beam members are end-to-end connected.
In addition to the above summary the following disclosure is detailed to insure adequacy and aid in understanding of the invention. This disclosure, however, is not intended to prejudice that purpose of a patent which is to cover each new inventive concept therein no matter how it may later be disguised by variations in form or additions of further improvements. For this reason there has been chosen a specific embodiment of the folding truss as adopted for use as a beam-like support member and showing a preferred means for opening and folding the truss.
This specific embodiment has been chosen for the purposes of illustration and description as shown in the accompanying drawing wherein:
BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 represents a side view of a fully opened folding truss assembly of this invention;
FIG. 2 represents a side view of the folding truss of FIG. 1 but in a partially folded condition, and
FIG. 3 represents a side view of the folding truss of FIG. 1 and 2 now in the fully folded condition.
In the following description and in the claims various details will be identified by specific names for convenience, these names, however, are intendedto be generic in their application. Corresponding reference characters refer to like members throughout the three figures of the drawing.
The drawing accompanying, and forming part of, this specification discloses certain details of construction for the purpose of explanation of the broader aspects of the invention, but it should be understood that structural details may be modified in various respects without departure from the concept and principles of the invention and that the invention may be incorporated in other structural forms than shown.
EMBODIMENT OF FIGS. 1, 2 and 3 Referring now to the preferred embodiment of FIG. 1 there is shown a folding truss which is depicted as being in its fully opened condition. The straight beam portion, as illustrated, includes four like members identified as 10, 11, 12 and 13. Member is hingedly attached at its right end to and by hinge 15 to the left end of member 11. Member 11 is hingedly attached at its right end to and by hinge 16 to the left end of member 12. Member 12, in turn, is hingedly attached to and at its right end by hinge 17 to the left end of member 13. In this preferred embodiment the pin of the hinges 15 and 17 are disposed above the beam members while the pin of the hinge 16 is located below the beam. Members 10, ll, 12 and 13 when in the straight condition become the beam member providing the tension or compression member.
Still referring to FIG. 1 it is to be noted that midlength of each of the members 10, 11, 12 and 13 are provided pivot pins 20, 21, 22 and 23. On these pins are pivotally mounted support arms 26, 27, 28 and 29. Arms 26 and 27 are pivotally connected at their ends by pin 32. The other or right end of arm 27 is pivotally connected to the left end of arm 28 by pin 34. The right end of arm 28 is pivotally connected to the left end of arm 29 by pin 36. A retaining bearing block 40 is pivotally mounted on arm 28 at a point a short distance from the pivot pin 36. A nut member 42 is pivotally mounted on support arm 29 at a short distance to the right of pivot pin 36. A lead screw member 44 is rotatably mounted in the bearing block 40 so as to be axially retained in this bearing block while the threaded portion of the screw is threadedly retained in the nut member 42 so as to move this nut member back and forth on the screw as the screw is rotated. A handle 46 is provided on the right or outer end of screw 44 to provide means for the screw to be rotated to cause nut 42 to be moved closer or further from the retaining bearing 40.
In FIG. 2, as seen, the folding truss or beam is in a partially folded condition wherein handle 46 has been turned to cause screw 44 to draw nut member 42 towards the bearing block 40. As this movement occurs the support arms 28 and 29 are drawn towards each other to provide a more acute angle between the arms. At the same time, arms 27 and 26 are drawn to a like more acute angle. As this occurs the beam portions 10, 11, 12 and 13 are caused to be moved from their open condition of FIG. 1 to the condition of FIG. 2. In this period of movement the members are moved around the hinge pins provided by hinges I5, 16 and 17. In the moving of the truss and the beam portions from its fully opened condition to the accordian condition of FIG. 2 the support beams 26, 27, 28 and 29 are equally moved to cause the other beams l0, l1, l2 and 13 to act in a standard sissor manner. It is to be noted that the arms 26, 27, 28 and 29 in their connected lengths are greater than the connected lengths of the members 10, ll, 12 and 13.
Referring now to FIG. 3 it is to be noted that the folding truss is in its substantially fully folded condition wherein the screw 44 has been turned to bring nut 42 and bearing 40 to a close proximity. In this view it is readily determined that the length of the arm portion 27 extending from pivot 32 to pivot pin 21 is greater than the distance of the beam member 11 extending from hinge 16 to the pivot pin 21. This same relationship of the beam member to the corresponding support arm occurs through the rest of the embodiment so that when the screw 44 is rotated to cause the truss to be brought to a fully opened condition as in FIG. 1 the support members remain in a zig-zag array while the beam members 10, 11, 12 and 13 are disposed in a straight line. In the fully closed condition of FIG. 3 the support arm members extend beyond the beam members.
USE AND OPERATION The truss of this invention provides means for providing support beam members which are connected as by through pins 20, 21, 22 and 23 or by means of other framing to a like truss whereby in a fully ex panded condition the two expanded units provide a tension or a compression support beam which may be supported at any two points. For example, at one end of the expanded unit and at one of the hinge points such as point 34 which may, for example, have a roller upon it. The uses for a folding truss, of course, is myriad. A preferred use is for a conveyor frame wherein the belt conveyor is to be collapsed for storage and/or transport as, for example, into a truck or onto a loading dock. As a support for a cover the supporting arms 26, 27, 28 and 29 may carry the flexible cover which may, for example, bea swimming pool cover. The truss in its fully opened condition in FIG. 1 carries the flexible covering on the pins 20, 32, 21, 34, etc., with the cover portion extending across the top of the swimming pool and in its collapsed condition the cover is caused to be folded to expose the pool to a normal use condition. Temporary bridges, walk-ways, platforms and the like, of course, may be supported by this folding truss. This folding principle may also be used to provide a boom or beam portion for a crane or the like.
It is also to be noted that instead of the screw 44, as
shown, it is possible to operate the folding of this mechanism by causing a cable to be attached to one of the pins such as pin 32 or 36 which will permit the weight to be supported while the folding truss is collapsed to the condition of FIG. 3. By means of an auxillary support and the attachment of one end of either beam member 10 or 13 to a fixed support the truss is enabled to be pulled to a fully opened condition or collapsed to a folded condition as desired.
The number of beam members is merely a matter of selection as is also their size and composition. A like number of support members are also needed with the support members being a greater length than the beam members. It is contemplated that with the beam members arranged in a straight line each support arm is at a slope angle which should be at least 20 so that the folding movement of the support arms will not be too difficult when causing the folding or unfolding to be done. Whether used in pairs or other multiples, the folding truss provides a beam member which may be folded when desired.
The hinges 15, 16 and 17 are shown as the preferred means for connecting the beam members 10, l1, l2 and 13 but it is to be noted that the beam members may instead be lapped with a common pin through both members, as shown, with pin 32 and members 26 and 27. It is to be noted that the beam members are to be pivotally or hingedly connected so as'to be moved into a straight line as in FIG. 1.
Terms such as left,"
tom, top, in
right, up, down, botout and the like are applicable to the embodiment shown and described in conjunction with the drawing. These terms are merely for the purposes of description and do not necessarily apply to the position in which the folding truss may be constructed or used.
While a particular embodiment of the truss has been shown and described it is to be understood the invention is not limited thereto since modifications may be made within the scope of the accompanying claims and protection is sought to the broadest extent the prior art allows.
What is claimed is:
1. A folding truss assembly comprising: (a) a mu]- tiplicity of like length beam members pivotally connected at their ends to each other in a series and adapted to be fully opened to form a straight line and when folded are brought next their adjacent members in an accordian-like manner; (b) a multiplicity of connecting arms comprising end and intermediate arms of the same number as the beam members, the connecting arms pivotally mounted on and at the mid-point of the beam members, said connecting arms also being pivotally connected to each other at their ends with the length of the intermediate connecting arm being greater than the beam member and the end connected arm portions being half the length of the intermediate connecting arm, any intermediate arm from its pivot connection on the beam member to the pivot connection with the next connecting arm being greater than the distance from the same pivot connection of the connecting arm on the beam member to the pivot connection of said beam member and to the pivot connection with the next beam member said connecting arms being disposed is a zig-zag manner when the beam members are opened to form a substantially straight line, (c) means (0) MEANS for moving the connecting arms around their pivoted connections so as to move the series of beam members from a straight condition to an accordion-like folded condition and vice versa.
2. A folding truss assembly as in claim I in which the beam members are hingedly connected at their ends so as to be disposed in an end-to-end relationship.
3. A folding truss assembly as in claim 1 in which the means for moving the connecting arms is a lead screw having one end rotatably mounted and axially retained in a bearing block pivotally connected to one support arm, said screw also having its threaded portion retained in a nut member pivotally secured to an adjacent support arm.
4. A folding truss assembly as in claim 3 in which the lead screw has a crank handle mounted on one end so that said screw may be rotated.
5. A folding truss assembly as in claim 1 in which the slope of the support arms to the axis of the full-extended, straight line beam members is an angle of at least 10.
6. A folding truss assembly as in claim 1 in which the slope of the support arms to the axis of the fully-extended straight line members is an angle of about 20.
7. A folding truss assembly as in claim 1 in which the ratio of the pivoted lengths ofa beam member to a connecting arm is about four to five.
@ 3 3 UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3 7 9 77 Dated May 1513 a V 973 Inventor(s) Raymond L. Hall- It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:
Please change address of Applicant to read as follows 8 Knollwood Trail, E.
Brookside, New Jersey 07926 In the Abstract, next to last line, change "30" to read Col. 6, line delete"(c)means" first occurrence and change "MEANS" to read means Signed and sealed this 20th day of November 1973.
EDWARD M FLETCHER JR RENE D TEGTMEYER J Attesting Officer Acting Commissioner of Patents