US2020544A

US2020544A - Folding sectional door

Info

Publication number: US2020544A
Application number: US614894A
Authority: US
Inventors: Charles C Gill; Verne L Julian; John W Mcilwraith; Charles F Rutledge
Original assignee: MCILWRAITH
Current assignee: MCILWRAITH
Priority date: 1932-06-02
Filing date: 1932-06-02
Publication date: 1935-11-12
Anticipated expiration: 1952-11-12

Description

Nov. 12, 1935. c. C. GILLETAL Y 2,0%,544

FOLDING SECTIONAL DOOR Filed June 2, 1952 2 Sheets-Sheet l 4a lq.. l A, P lq. Q

- IZ /4 5 'b a3 ATTORNEY.

-Nojn l2, 1935.

FOLDING SECT'I ONAL DOOR Filed June 2, 1952 2 Sheets-Sheet 2 ATTORNEYS.

Patented Nov. 12, 1935 UNITED srarss PATENT OFHQE FOLDING SECTIONAL DOOR Application June 2, 1932, Serial No. 614,894

29 Claims.

This invention relates to improvements in ilexible doors..

This invention also is an improvement upon the invention disclosed in the application of Charles F. Rutledge, entitled Flexible doors, filed November28, 1930, Serial No. 498,698.

The chief object of the/invention is to provide a structure wherein the parts are relatively automatic in their coaction and wherein certain parts automatically assume different positions for different positions of other parts for subsequent coaction with certain other parts.

One feature of the invention consists in the double socket for assisting in the retention in the Overhead position of the door sections.

Another feature of the invention consists in the pivoted track or switch track construction.

Another feature of the invention consists in the pivotal mounting of the cable connecting the counter-balancing mechanism and the door sections whereby the strain upon the cable is reduced to a minimum.

Still another feature of the invention consists in the interweaving of the cable with certain of the guide supports whereby the cable through the counter-balancing means exerts a lateral or opening force upon the guide supports to secure so-calleol breaking of the sections.

Still a further feature of the invention consists in the provision of a positive means for securing breaking of the door sections.

The invention contemplates the employment of a plurality of pairs, and preferably four, of door sections hingedly connected together and so arranged that the initial movement of all the sections is upwardly and each superposed pair of sections is successively folded as it approaches the overhead position but not theretofcre.

The full nature of the invention will be understood from the accompanying drawings and the following description and claims:

Fig. l is a side elevational view of one form of the track and counter-balancing structure at one side of the door, the guide means associated with the track being shown dotted and the door sections being shown dotted and in the door closing position. Fig. 2 is a similarview with the door sections shown in full and in the overhead or open door position. Fig. 3 is a View similar to Fig. l of the upper portion of one of the track structures, with the guides of the first door section shown in the initial opening position. Fig. 4 is a similar view of the same parts in a successive position. Fig. 5 is a similar View of also includes the guides carried by an intermed iate door section. Fig. 6 is a similar view of the parts shown in Fig. 5 showing them in a successive position. Fig. '7 is a similar view showing the position of all of the guides and track in 5 a succeeding position and preliminary to final overhead positioning of the parts. Fig. 8 shows the parts illustrated in Fig. 7 in a position just prior to the final position shown assumed by the parts in Fig. 2; Fig. 9 is a View similar to Fig. 2 and of a modied form of the invention, the full lines showing the door in closed position and the dotted lines showing the door and associated structure in the open position. Fig. l0 is a rear View of one end of 15 the door and associated mechanism in the closed position.

In the drawings, there is illustrated but one trackway structure and one end of the door associated therewith. It is to be understood that the 20.

structure, however, includes confronting track- Ways atreach side of the door such as is disclosed in the application before mentioned.

In the drawings l0 indicates a channel shaped vertical trackway extending from the bottom or 25 oor Il and terminating in an overhead head structure l2. The head structure l2 suitably supports as upon a pivot i3, a pulley I4 positioned in a housing i5 herein shown integral with the head structure and forwardly of the track structure, reference being had to the plane including the closed door sections and the opposed or confronting trackways. The door is herein illustrated as comprised of a plurality of door sections, l indicating the upper section pivotally connected at its lower edge as at ll to a second section ES pivotally connected at its lower edge as at I9 to a third section 26, in turn, pivotally connected at its lower edge 2| to a bottom section 22.

The cable 23 is suitably secured at one end to a stationary connection as at 24 and passes through a pulley 25 and thence over pulley I4 and at its opposite end is secured as at 26 to the lower door section a slight distance above the bottom of the door. Pulley 25 is associated with suitable counter-balancing means herein shown in the form of a coil spring 21, one end being secured to the pulley hanger or hous- 4. ing 28 and its lower end being suitably anchored 50 as at 29.

The door sections at each side are provided with the following guide means, and a description of one side will suflice for an understanding of both opposite arrangements. Suitably supported upon or adjacent the upper edge of the upper door section I6 is a support or pintle 35 which mounts a guide roller 3|. Intermediate the ends or upper and lower edges of the upper door section I3 is another pintle 32 which pivotally supports a guide roller 33. The second and third sections, substantially co-incidental with the hinge, support a pintle 34 which mounts a guide roller 35 and intermediate the upper and lower edges of the third section, there is a pintle 35 that supports a guide roller 31, the distance between the

pintles

34 and 36 being less than the distance between the pintles 30 and 32, the lower end of the lowermost door section, or adjacent thereto, supports the pintle 38 that mounts the guide roller 39.

The head structure includes an upward extension 43 of the forward edge of the channel track lil or its equivalent and the same terminates in an upper socket 4I and a socket 42 immediately therebeneath. Socket 4| includes an inward extension 43 and a downwardly directed camming portion 44 that terminates in a vertical portion 45 which lies in substantial alignment with the other or rear vertical portion of the channel track ID, but is spaced therefrom. The other vertical portion of the track I0 has a continuation formed in the head structure which extends upwardly and rearwardly as at 46 and the same terminates in a Vertical portion 41 capped by an oiset and forwardly directed portion 48, the same lying an appreciable distance above the socket 4|. Pivotally supported in the gap between the lower end of the portion 45 and the upper end of the vertical portion of the track I8 in vertical alignment therewith at 43 is a switching track member that is pivotally supported upon the head structure. The tiltable switching track includes a depending portion 5|) and two arm portions 5| and 52 and, if desired, this structure may have added thereto suitable weighting 53 whereby the switch track when tilted upon its pivot will be so balanced that the center of gravity will lie upon one side or the other of `the pivot 49 and thereby said track will be maintained in the tilted position.

Pivotally supported as at 54 upon the head Structure is another combination switch and track member 55.

The operation of the device will be clearly evident from an examination of Figs. 1 to 8, inclusive. When the door is elevated, the counterbalancing in the form of the spring 21 becomes effective andthe roller 3| normally positioned between the two

parallel portions

48 and 45 is caused to move vertically until roller 3| engages the curved portion 44 and the top 43 and thus continued movement causes the roller to move forwardly and upwardly into the socket 4|. Continued upward movement on the door causes the iirst intermediate roller 33 to engage the track extension 53 of the first tiltable switch and the door section I6 is caused to move out of the vertical plane of the door opening and to move upwardly. This movement, of course, carries with it door section I8 so that the door section ES and the lower portion of door section I6 move rearwardly from the plane of the door opening. In the continued door opening movement, the roller 33 engages portion 52 of the iirst mentioned tiltable switch construction and tilts the switch member from the position shown in Fig. 3 to the position shown in Fig. 4. Since the switchY member 55 is normally constrained by reason of gravity into the position shown in Figs. 1 and 3, the roller 33 in its continued movement rides along the track portion 45 and passes between the track portion 46 and the switch member 55. This is shown in Fig. 5.

Just prior to this portion of the movement, the 5 roller 35 (see Fig. 4) has moved upwardly to the bottom of the gap between the inside Vertical portion of channel l0 and the lower end of track 45 and since the counterweighted overcenter operable track switch member has been 10 tilted into the position shown in Fig. 4, the roller 35 bea-rs on the right hand portion of the extension 53 of said switch structure, and the roller 35 continues its vertical movement. Continued vertical door movement causes the roller 15 35 to engage the portion 5| (see Fig. 5) of this iirst mentioned switch track and tilts the switch track into the initial position.

The roller 31, as the sections continue elevating, engages the left hand side of the switch 20 member 50 and the roller is switched rearwardly following the roller 33. This position is shown in Fig. 6. Continued upward movement of the door sections causes the roller 33 to engage the tail portion 55a of the switch track 25 55 and tilts said track member clockwise into the position shown in Fig. '7. Continued upward movement of the door sections causes the roller 35 to seat in the socket 42 and the roller 31 to engage the right hand portion of the switch 30 track member 55, the same being held in the position shown in Fig. 7 by the roller 33.

Continued upward movement of the door causes the lowermost roller 3S to move vertically and lie beneath the superposed rollers 3| and 35. 35 Y 'I'his action is permitted because the iirst mentioned switch track has been tilted from the position shown in Fig. 6 to the position shown in Fig. 7 by the roller 31 in its upward movement. In

other words, each roller progressively conditions 40 the rst switch member for successive roller guidance and the roller 33 also conditions the second successive switch 55. To prevent overhead positioning and tilting beyond the horizontal to any appreciable degree, the stop 48 is provided. This 45Y 39 engages the portion 50 of the rst mentioned 50 switch track and tilts the same into substantial alignment with the track portions ID and 45. Roller 31 in descending, clears the portion 52 of the iirst mentioned track just as roller 39 cleared the portion 5|, but engages portion 5E] and moves 55 the same from the position shown in Fig. 4 or the vertical aligned position, into the lateral position as shown in Figs. 1, 2, 3, 5, 6, and 8.

Continued lowering movement of the door sections permits the roller 35 to move downwardly 60 and it engages, in turn, the track portion 50 of the switch member a-nd tilts said member clockwise into the position corresponding to Figs. 4 and '1. The roller 33, in its lowering movement, engages the member 55 and moves it from the 65 position shown in Figs. 7 and 8 into the position shown in Figs. l, 3, 5, and 6 and the roller 33 then passes by the portion 52 of the rst mentioned track switch and conditions the track switch for subsequent reverse travel of roller 33. Due to the counterweighting 53, this switch is maintained in this position. The roller 3| in this movement of the roller 33, has moved out of the socket 4| and moved downwardly into the position shown in dotted lines in Fig. 1. 15

In Figs. 9 and 10, there is illurated a modified form of the invention and in this figure, similar or like parts are indicated by similar numerals of the I @I3 series. Thus, superposed door sections are indicated by the numerals Il, IIS, I2, and Iif. The uppermost guide is indicated by the numeral ISI, the intermediate guide carried by the uppermost section by the numeral |33, the next lowest guide between the two intermediate sections bythe numeral I35, the intermediate guide carried by the third section intermediate its ends by the numeral ll and the lowermost section supported guide by the numeral ISS.

- The pivoted supports therefor, are indicated by the numerals 36, IZ, i315, ISE, and I38. The cable IES is suitably secured as at to the lowermost door section and is herein shown passing in front of the guide support I36, behind the guide support Iiili, in front of the guide support I32 and behind the guide support Ie. The cable I23 passes over the pulley II fi in the carrier H5 piv- ,and

otally supported at I I3 upon an extension Ida of the stop ii carried by the head structure I I2, the latter being a continuation of the track I III. The track I Iii, near its upper end and in vertical alignment but slightly offset therefrom, includes the uppermost socket IlI and the socket M2 immeiately therebeneath. The track has the top portion I 33, the inclined camming portion I 44 and the depending vertical portion 45, latter in substantial alignment with the inner and rear wall of the channel track Iiii but spaced thereform and forming a gap or opening therewith. This inner or rear wall of channel I II) is extended upwardly and rearwardly as a part of the head structure and the same is indicated by the numeral MI5 and terminates in the vertical portion Mil. Pivotally supported upon the head structure as at IEB is the switch track member |55 having the upper portion I55a which, when engaged by roller E33, assumes a vertical position.

It will be apparent from a comparison of Figs. l and 2 with Figs. 9 and l() that the rst switch structure shown in the before mentioned figures is omitted from the present structure and the interweaving of the cable with the guide supports constitutes the equivalent means for causing the sections to break in the gap in the track IB and thus insures the folding of the door sections as successive pairs of sections approach the overhead position.

'I'o positively insure such breaking of the joints or door sections at each side of the door, there may be mounted upon or adjacent the track II@ a cam or block IBG which may, if desired, be of rubber so that if there be excessive counter-balancing, this member will take the shock and slow down the opening movement. The second door section includes a cam engaging portion I8I that is positioned in spaced relation to the door section supporting the same by the arm I 82. The lowermcst door section includes a similar cam engaging member i533 supported by the portion its. As illustrated, the interior or cam engaging portion is curved as at E55. 'As the sections are elevated, each of the cam engaging members I8I w3 respectively, successively engage the member iii and the joints are broken. Each side of the door is provided with the same structure so that uniform operation will be obtained therefrom.

It will be noted that in Figs. 9 and i0, the sup- Y port for the pulley is offset from vertical alignment of the track Il@ while in Figs. land 2, the support for the pulley is offset from the plane of the track lil, but the offset is opposite, to-wit:

Y of the door opening. No interweaving of the cable is employed with the pulley mounting shown in Figs. 1 and 2, and with the universal mounting of the cable supporting pulley, interweaving of the cable can be obtained.

In these forms of the invention, thereby differing from the co-pending application, all the guide rollers upon one side of the door lie in substantially the came Vertical plane.

The invention claimed is:

1. In a folding door structure, the combination of a, plurality of pairs of door sections horizontally hinged together and arranged for folding and movable upwardly into an overhead folded position, the remote edges of ghingedly connected pairs of doors` being initially movable upwardly in substantially the same plane, a trackway for said door sections and at each side of the door, guide members associated with the sections and the trackway at each side of the door, means supporting said guide members and projecting beyond the ends of the door sections, counterbalancing means for said door sections, and a single cable at each side of the door having one end associated with the door sections and alternately positioned forwardly and rearwardly of the successive projecting portions of said guide supporting means for the purpose set forth.

2. In a folding door structure, the combination of a plurality of pairs of door sections horizontally hinged together and varranged for folding and movable upwardly into an overhead folded position, the remote edges of hingedly connected pairs of doors being initially movable upwardly in substantially the same plane, a trackway for said door sections and at each side of the door, guide members associated with the sections and the trackway at each side of the door, means supporting said guide members and projecting beyond the ends of the door sections, counterbalancing means for said door sections, and a single cable at each side of the door having one end associated with the door sections and alternately positioned forwardly and rearwardly of the successive projecting portions of said guide supporting means for the purpose set forth, a pulley associated with said cable and in overhead relation with respect to the door when closed and laterally offset from the trackway.

3. In a folding door structure, the combination of a plurality of pairs of door sections horizontally hinged together and arranged for folding and movable upwardly into an overhead folded position, the remote edges of hingedly connected pairs of doors being initially movable upwardly in substantially the same plane, a trackway for said door sections and at each side of the door, guide members associated with the sections and the trackway at each side of the door, means supporting said guide members and projecting beyond the ends of the door sections, counterbalancing means for said door sections, a single cable at each side of the door having one end associated with the door sections and alternately positioned forwardly and rearwardly of the successive projecting portions of said guide supporting means for the purpose set forth, a pulley associated with said cable and in overhead relation with respect to the doc-r when closed and laterally offset from the trackway, and means swingably supporting said pulley for the purpose set forth.

4. In a folding door structure, the combination of a plurality of horizontally foldable door sections hingedly connected together and arranged for folding and movable upwardly into an overhead folded position, a vertical trackway at each Side of the door opening, guide supports projecting into said trackway from the lateral edges of the door sections, guides carried by said supports and movable in said trackway, a head structure communicating at its lower end with the upper end of the Vertical trackway and including at its upper end a pair of superposed pockets slightly offset laterally from the trackway and communicating therewith, and an upwardly and rearwardly directed track portion carried by the head structure and forming an extension of the vertical trackway, said last mentioned extension being operatively associated with alternate guides in the folding of the door sections and to secure the seating oi the other alternate guides in said pockets.

5. In a folding door structure, the combination of a plurality of horizontally foldable door sections hingedly connected together and arranged for folding and movable upwardly into an overhead folded position, a vertical trackway at each side of the door opening, guide supports projecting into said trackway from the lateral edges of the door sections, guides carried by said supports and movable in said trackway, a head structure communicating at its lower end with the upper end of the vertical trackway and including at its upper end a pair of superposed pockets slightly Offs-et laterally from the trackway and communieating therewith, an upwardly and rearwardly directed track portion carriedrby the head structure and forming an extension of the vertical trackway, said last mentioned extension being operatively associated with alternate guides in the folding of the door sections and to secure the seating of the other alternate guides in said pockets, and a pivoted track member pivotally supported near the upper end of said track extension and arranged for engagement by alternate guides and upon opposite sides.

G. In a folding door structure, the combination of a plurality of horizontally foldable door sections hingedly connected together and arranged for folding and movable upwardly into an overhead folded position, a vertical trackway at each side of the door opening, guide supports projecting into said trackway from the lateral edges of the door sections, guides carried by said supports and movable in said trackway, a head structure communicating at its lower end with the upper end of the vertical trackway and including at its upper end a pair of superposed pockets slightly offset laterally from the trackway and communicating therewith, an upwardly and rearwardly directed track portion carried by the head structure and forming an extension of the vertical trackway, said last mentioned eX- tension being operatively associated with alternate guides in the folding of the door sections and to secure the seating of the other alternate guides in said pockets, and a pivoted switch track pivotally supported by said head structure adjacent the connection thereof with the vertical trackway and having a track portion arranged for movement into the trackway for rearward guidance of alternate guides and for movement out of the trackway for upward vertical movement of other and alternate guides.

7. In a folding door structure, the combination of a plurality of horizontally foldable door sections hingedly connected together and arranged for folding and movable upwardly into an overhead folded position, a vertical trackway at each side of the door opening, guide supports projecting into said trackway on the end of the door sections, guides carried by said supports and movable in said trackway, a head structure communicating at its lower end with the upper end of the vertical trackway and including at its upper end a pair of superposed pockets slightly offset laterally from the trackway and communieating therewith, an upwardly and rearwardly directed track portion carried by the head structure and forming an extension of the vertical trackway, said last mentioned extension being operatively associated with alternate guides in the folding of the door sections and to secure the seating of the other alternate guides in said pockets, a pivoted track member pivotally supported near the upper end of said track extension and arranged for engagement by alternate guides and upon opposite sides, and a pivoted switch track pivotally supported by said head structure adjacent the connection thereof with the vertical trackway and having a track portion arranged for movement into the trackway for rearward guidance of alternate guides and for movement out of the trackway for upward vertical movement of other and alternate guides.

8. In a folding door structure, the combination of a plurality of horizontally foldable door sections hingedly connected together and arranged fcr folding and movable upwardly into an overhead folded position, a vertical trackway at each side of the door opening, guide supports projecting into said trackway on the end of the door sections, guides carried by said supports and movable in said trackway, a head structure communicating at its lower end with the upper end of the vertical trackway and including at its upper end a pair of superposed pockets slightly offset laterally from the trackway and communicating therewith, an upwardly and rearwardly directed track portion carried by the head structure and forming an extension of the vertical trackway, said last mentioned extension being operatively associated with alternate guides in the folding of the door sections and to secure the seating of the other alternate guides in said pockets, and a pivoted switch track pivotally supported by said head structure adjacent the connection thereof with the vertical trackway and having a track portion arranged for movement into the trackway for rearward guidance of alternate guides and for movement out of the trackway for upward vertical movement of other and alternate guides, said switch track member being of the over-center operable type and successively engageable by successive rollers for alternate movement into and out of the trackway,

9. In a folding door structure, the combination of a plurality of horizontally foldable door sections hinffedly connected together and arranged for folding and movable upwardly into an overhead folded position, a vertical trackway at each side of the door opening, guide supports projecting into said trackway on the end of the door sections, guides carried by said supports and movable in said trackway, a head structure communicating at its lower end with the upper end of the vertical trackway and including at its upper end a pair of superposed pockets slightly oiset laterally from the trackway and communieating therewith, an upwardly and rearwardly directed track portion carried by the head structure and forming an extension of the vertical trackway, said last mentioned extension being operatively associated with alternate guides in the folding of the door sections and to secure the seating of the other alternate guides in said pockets, a pivoted track member pivotally supported near the upper end of said track extension and arranged for engagement by alternate guides and upon opposite sides, and a pivoted switch track pivotally supported by said head structure adjacent the connection thereof with the vertical trackway and having a track portion arranged for movement into the trackway for rearward guidance of alternate guides and for movement out of the trackway for upward vertical movement of other and alternate guides, said switch track member being of the over-center operable type and successively engagable by successive guides for alternate movement into and out of the ltrackway.

10. in a folding door structure, the combination of a plurality of horizontally foldable door sections hingedly connected together and arranged for folding and movable upwardly into an overhead folded position, the hingedly connected pairs of doors being initially movable upwardly in substantially the same plane, a vertical trackway at each side of the door opening, guide supports projecting into said trackway and on the ends of certain door sections, guides carried by said supports and movable in said trackway, counter-balancing means for said door sections, a single cable at each side of the door associated with the counter-balancing means and the door sections and. alternately positioned forwardly and rearwardly of successive guide supports for' the purpose set forth, a head structure communicating at its lower end with the upper end of the vertical trackway and including at its upper end a pair of superposed pockets slightly offset laterally from the trackway and communicating therewith, and an upwardly and rearwardly directd track portion carried by the head structure and forming an extension of the vertical trackway, said last mentioned extension being operatively associated with alternate guides in the folding of the door sections and to secure the seating of the other alternate guides in said pockets.

ll. In a folding door structure, the combination o-f a plurality of horizontally foldable door sections hingedly connected together and arranged for folding and movable upwardly into an overhead folded position, the hingedly connected pairs of doors being initially movable upwardly in substantially the same plane, a vertical trackway at each side of the door opening, guide supports projecting into said trackway and on the ends of certain door sections, guides carried by said supports and movable in said trackway, counter-balancing means for said door sections, a single cable at each side of the door associated with the counter-balancing means and the door sections and alternately positioned forwardly and` rearwardly of successive guide supports for the purpose set forth, a head structure communicating at its lower end with the upper end of the vertical trackway and including at its upper end a pair of superposed pockets slightly offset laterally from the trackway and communicating therewith, an upwardly and rearwardly directed track portion carried by the head structure and forming an extension of the vertical trackway,

said last mentioned extension being operatively associated with alternate guides in the folding of the door sections and to secure the seating of the other alternate guides in said pockets, and a pivoted track member pivotally supported near the upper end of said track extension and arranged for engagement by alternate guides upon opposite sides.

12. In a folding door structure, the combination of a plurality of horizontally foldable door sections hingedly connected together and arranged for folding and movable upwardly into an overhead folded position, the hingedly connected pairs of doors being initially movable upwardly in substantially the same plane, a vertical trackway at each side of thedoor opening, guide supports projecting into said trackway and on the ends of certain door sections, guides carried by said supports and movable in said trackway, counter-balancing means for said door sections, a single cable at each side of the door associated with the counter-balancing means and the door sections and alternately positioned forwardly and rearwardly of successive guide supports for the purpose set forth, a head structure communicating at its lower end with the upper end of the vertical trackway and including at its upper end l a pair of superposed pockets slightly offset laterally from the trackway and communicating therewith, an upwardly and rearwardly directing track portion carried by the head structure and forming an extension of the vertical trackway, said last mentioned extension being operatively associated with alternate guides in the folding of the door sections and to secure the seating of the other alternate guides in said pockets, and a pivoted switch track pivotally supported by said head structure adjacent the connection thereof with a vertical trackway and having a track portion arranged for movement into the trackway for rearward guidance of alternate guides and for movement out of the trackway for upwardly vertical movement of other and alternate guides.

13. In a foldingdoor structure, the combination of a plurality of horizontally foldable door sections hingedly connected together and arranged for folding and movable upwardly into an overhead folded position, the hingedly connected pairs of doors being initially movable upwardly in substantially the same plane, a vertical trackway at each side of the door opening, guide supports projecting into said trackway and on the ends of certain door sections, guides carried by said supports and movable in said trackway, counter-balancing means for said door sections, a single cable at each Side of the door associated with the counter-balancing means the door sections and alternately positioned forwardly and rearwardly of the successive guide supports for the purpose set forth, a head-structure communicating at its lower end with the upper end of the vertical trackway and including a pair of superposed pockets in alignment with said trackway although slightly offset laterally from the trackway and communicating' therewith, an upwardly and rearwardly directed track portion carried by the head structure and forming an extension of the vertical trackway, said last mentioned extension being operatively associated with alternate guides in the folding of the door sections and to secure the seating of the other alternate guides in said pockets, a pivoted track member pivotally supported near the upper end of said track extension and arranged for engagement by alternate guides upon opposite sides, and a pivoted switch track pivotally supported by said head structure adjacent the connection thereof with a vertical trackway and having a track portion arranged for movement into the trackway for rearward guidance of the alternate guides last mentioned and for movement out of the trackway for upwardly vertical movement of other and alternate guides.

14. In a folding door structure, the combination of a plurality of horizontally foldable door sections hingedly connected together and arranged for folding and movable upwardly into an overhead folded position, a vertical trackway at each side of the door opening, guide supports projecting into said trackway from the lateral edges of the door sections, guides carried by said supports and movable in said trackway, a head structure communicating at its lower end with the upper end of the vertical trackway and including at its upper end a pair of superposed pockets slightly offset laterally from the trackway and communicating therewith, an upwardly and rearwardly vdirected track portion carried by the head structure and forming an extension of the vertical trackway, said last mentioned extension being operatively associated with alternate guides in the folding of the door sections and to secure the seating of the other alternate guides in said pockets, and means cooperating with the door sections for facilitating the breaking thereof into folded relation in the upward movement of the sections.

15. In a folding door structure, the combination of a plurality of horizontally foldable door sections hingedly connected together and arranged for folding and movable upwardly into an overhead folded position, a vertical trackway at each side of the door opening, guide supports projecting into said trackway from the lateral edges of the door sections, guides carried by said supports and movable in said trackway, a head structure communicating at its lower end with the upper end of the vertical trackway and including at its upper end a pair of superposed pockets slightly offset laterally from the trackway and communicating therewith, an upwardly and rearwardly directed track portion carried by the head structure and forming an extension of the vertical trackway, said last mentioned extension being operatively associated with alternate guides in the folding of the door sections and to secure the seating of the other alternate guides in said pockets, a pivoted track member pivotally supported near the upper end of said track extension and arranged for engagement by alternate guides and upon opposite sides, and means cooperating with the door sections for facilitating the breaking thereof into folded relation in the upward movement of the sections.

16. In a folding door structure, the combination of a plurality of horizontally foldable door sections hingedly connected together and arranged for folding and movable upwardly into an overhead folded position, the hingedly connected pairs of doors being initially movable upwardly in substantially the same plane, a vertical trackway at each side of the door opening, guide supports projecting into said trackway and on the ends of certain door sections, guides carried by said supports and movable in said trackway, counterbalancing means for said door sections, a single cable at each side of the door associated with the counterbalancing means and the door sections and alternately positioned forwardly and rearwardly of successive guide supports for the purpose set forth,

a head structure communicating at its lower end with the upper end of the vertical trackway and including at its upper end a pair of superposed pockets slightly offset laterally from the trackway and communicating therewith, an upwardly and rearwardly directed track portion carried by the head structure and forming an extension of the vertical trackway, said last mentioned extension being operatively associated with alternate guides in the folding of the door sections and to secure the seating of the other alternate guides in said pockets, and means cooperating with the door sections for facilitating the breaking thereof into folded relation in the upward movement of the sections.

17. In a folding door structure, the combination of a plurality of horizontally foldable door sections hingedly connected together and arranged for folding and movable upwardly into an overhead folded position, the hingedly connected pairs of doors being initially movable upwardly in substantially the same plane, a vertical trackway at each side of the door opening, guide supports projecting into said trackway and on the ends of certain door sections, guides carried by said supports and movable in said trackway, counterbalancing means for said door sections, a single cable at each side of the door associated with the counterbalancing means and the door sections and alternately positioned forwardly and rearwardly of successive guide supports for the purpose set forth, a head structure communicating at its lower end with the upper end of the vertical trackway and including at its upper end a pair of superposed pockets slightly offset from the trackway and communicating therewith, an upwardly and rearwardly directed track portion carried by the head structure and forming an extension of the vertical trackway, said last mentioned extension being operatively associated with alternate guides in the folding of the door sections and to secure the seating of the other alternate guides in said pockets, a pivoted track member pivotally supported near the upper end of said track extension and arranged for engagement by alternate guides upon opposite sides, and means cooperating with the door sections for facilitating the breaking thereof into folded relation in the upward movement of the sections.

18. In a folding door structure, the combination of a plurality of horizontally foldable door sections hingedly connected together and arranged for folding and movable upwardly into an overhead folded position, the hingedly connected pairs of doors being initially movable upwardly in substantially the same plane, a vertical trackway at each side of the door opening, guide supports projecting into said trackway and on the ends of certain door sections, guides carried by said supports and movable in said trackway, counter-balancing means for said door sections, a single cable at each side of the door associated with the counterbalancing means and the door sections and alternately positioned forwardly and rearwardly of successive guide supports for the purpose set forth, a head structure communicating at its lower end with the upper end of the vertical trackway and including at its upper end a pair of superposed pockets slightly offset laterally from the trackway and communicating therewith, an upwardly and rearwardly directed track portion carried by .the head structure and forming an extension of the vertical trackway, said last mentioned extension being operatively associated with alternate vguides in the folding ofl the door sections and to secure the seating of the other alternate guides in said pockets, and a pulley associated with said cable and in overhead relation with respect to the door when closed and laterally offset from the trackway.

19. In a folding door structure, the combination of a plurality of horizontally foldable door sections hingedly connected together and arranged for folding and movable upwardly into an overhead folded position, the hingedly connected pairs of doors being initially movable upwardly in substantially the same plane, a vertical trackway at each side of the door opening, guide supports projecting into said trackway and on the ends of certain door sections, guides carried by said supports and movable in said trackway, counterbalancing means for said door sections, a single cable at each side of the door associated with the counterbalancing means and the door sections and alternately positioned forwardly and rearwardly of successive guide supports for the purpose set forth, a head structure communicating at its lower end with the upper end of the vertical trackway and including at its upper end a pair of superposed pockets slightly offset from the trackway and communicating therewith, an upwardly and rearwardly directed track portion carried by the head structure and forming an extension of the vertical trackwav,l Said last mentioned extension being operatively associated with alternate guides in the folding of the door sections and to secure the seating of the other alternate guides in said pockets, a pivoted track member pivotally supported near the upper end of said track eXten- -sion and arranged for engagement by alternate lsections hingedly connected together and arranged for folding and movable upwardly into an overhead folded position, a vertical trackway at each side of the door opening, guide supports projecting into said trackway from the lateral edges of the door sections, guides carried by said supports and movable in said trackway, a head structure communicating at its lower end with the upper end of the vertical trackway and including at its upper end a pair of superposed pockets slightly offset laterally from the trackway and communicating therewith, an upwardly and rearwardly directed track portion carried by the head structure and forming an extension of the vertical trackway, said last mentioned extension being operatively associated with alternate guides in the folding of the door sections and to secure the seating of the other alternate guides in said pockets, means cooperating with the door sections for facilitating the breaking thereof into folded `relation in the upward movement of the sections, and a pulley associated with said cable and in overhead relation with respect to the door when closed and laterally offset from the trackway.

2l. in a folding door structure, the combination of a plurality of horizontally foldable door sections hingedly connected together and arranged for folding and movable upwardly into an overhead folded position, a vertical trackway at each side of the door opening, guide supports projecting into said trackway from the lateral edges of the door sections, guides carried by said supports A and movable in' said trackway, a head structure communicating at its lower end with the upper Vend of the vertical trackway and including at its upper end a pair of superposed pockets slightly offset laterally from the trackway and communieating therewith, an upwardly and rearwardly directed track portion carried by the head structure and forming an extension of the vertical trackway, said last mentioned extension being operatively associated with alternate guides in the folding of the door sections and to secure the seating of the other alternate guides in said pockets, a pivoted track member pivotally supported near the upper end of said track extension and arranged for engagement by alternate guides and upon opposite sides, means cooperating with the door sections for facilitating the breaking thereof into folded relation in the upward movement of the sections, and a pulley associated with said cable and in overhead relation with respect to the door when closed and laterally offset from the trackway.

22. In a folding door structure, the combination of a plurality of horizontally foldable door sections hingedly connected together and arranged for folding and movable upwardly into an overhead folded position, the hingedly connected pairs of doors being initially movable upwardly in substantially the same plane, a Vertical trackway at each side of the door opening, guide supports projecting into said trackway and on the ends of certain door sections, guides carried by said supports and movable in said trackway, counterbalancing means for said door sections, a single cable .at each side of the door associated with the counterbalancing means and the door sections and alternately positioned forwardly and rearwardly of successive guide supports for the purpose set forth, a head structure communicating ,at its lower end with the upper end of the vertical trackway and including at its upper end a pair of superposed pockets slightly offset laterally from the trackway and communicating therewith, an upwardly and rearwardly directed track portion carried by the head structure and forming an extension of the vertical trackway, said last mentioned extension being operatively associated with alternate guides in the folding of the door sections and to secure the seating of the other alternate guides in said pockets, means cooperating with the door sections for facilitating the breaking thereof into folded relation in the upward movement of the sections, and a pulley associa-ted with said cable and in overhead relation with respect to the door when closed and laterally offset from the trackway.

23. In a folding door structure, the combination of a plurality of horizontally foldable door sections hingedly connected together and arranged for folding and movable upwardly into an overhead folded position, the hingedly connected pairs of doors being initially movable upwardly in substantially the same plane, a vertical trackway at each side of the door opening, guide supports projecting into said trackway and on the ends of certain door sections, guides carried by said supports and movable in said trackway, counterbalancing means for said door sections, a single cable at each side of the door associated with the counterbalancing means and the door sections and alternately positioned forwardly and rearwardly of successive guide supports for the purpose set forth, a head structure communieating at its lower end with the upper end ofV end a pair of superposed pockets slightly offset from the trackway and communicating therewith, an upwardly and rearwardly directed track portion carried by the head structure and forming an extension of the vertical trackway, said last mentioned extension being operatively associated with alternate guides in the folding of the door sections and to secure the seating of the other alternate guides in said pockets, a pivoted track member pivotally supported near the upper end of said track extension and arranged for engagement by alternate guides upon opposite sides, means cooperating with the door sections for facilitating the breaking thereof into folded relation in the upward movement of the sections, and a pulley associated with said cable and in overhead relation with respect to the door when closed and laterally oifset from the trackway.

24. In a folding door structure, the combination of a plurality of horizontally foldable door sections hingedly connected together and arranged for folding and movable upwardly into an overhead folded position, the hingedly connected pairs of doors being initially movable upwardly in substantially the same plane, a vertical trackway at each side of the door opening, guide supports projecting into said trackway and on the ends of certain door sections, guides carried by said supports and movable in said trackway, counterbalancing means for said door sections, a single cable at each side of the door associated with the counterbalancing means and the door sections and alternately positioned forwardly and rearwardly of successive guide supports for the purpose set forth, a head structure communicating at its lower end with the upper end of the vertical trackway and including at its upper end a pair of superposed pockets slightly oifset laterally from the trackway and communicating therewith, an upwardly and rearwardly directed track portion carried by the head structure and forming an extension of the vertical trackway, said last mentioned extension being operatively associated with alternate guides in the folding of the door sections and to secure the seating of the other alternate guides in said pockets, a pulley associated with said cable and in overhead relation with respect to the door when closed and laterally offset from the trackway, and means swivably supporting said pulley for the purpose set forth.

25. In a folding door structure, the combination of a plurality of horizontally foldable door sections hingedly connected together and arranged for folding and movable upwardly into an overhead folded position, the hingedly connected pairs of doors being initially movable upwardly in substantially the saine plane, a vertical trackway at each side of the door opening, guide supports projecting into said trackway and on the ends of certain door sections, guides carried by said supports and movable in said trackway, counterbalancing means for said door sections, a single cable at each side of the door associated with the counterbalancing means and the door sections and alternately positioned forwardly and rearwardly of successive guide supports for the purpose set forth, a head structure communicating at its lower end with the upper end of the vertical trackway and including at `its upper end a pair of superposed pockets slightly offset from the trackway and communicating therewith, an upwardly and rearwardly directed track portion carried by the head structure and forming an extension of the vertical trackway, said last mentioned extension being operatively associated with alternate guides in the folding of the door sections and to secure the seating of the other alternate guides in said pockets, a pivoted track member pivotally supported near the upper end of said track extension and arranged for engagement by alternate guides upon opposite sides, a pulley associated with said cable and in overhead relation with respect to the door when closed and laterally odset from the trackway, and means swivably supporting said pulley for the purpose set forth.

26. In a folding door structure, the combination of a plurality of horizontally foldable door sections hingedly connected together and arl edges of the door sections, guides carried by said l supports and movable in said trackway, a head structure communicating at its lower end with the upper end of the vertical trackway and including at its upper end a pair of superposed pockets slightly cifset laterally from the trackway and communicating therewith, an upwardly and rearwardly directed track portion carried by the head structure and forming an extension of the vertical trackway, said last mentioned extension being operatively associated with alternate guides in the folding of the door sections and to secure the seating of the other alternate guides in said pockets, means cooperating with the door sections for facilitating the breaking thereof into folded relation in the upward movement of the sections, a pulley associated with said cable and in overhead relation with respect to the door when closed and laterally offset from the trackway, and means swivably supporting said pulley for the purpose set forth.

27 In a folding door structure, the combination of a plurality of horizontally foldable door sections hingedly connected together and arranged for folding and movable upwardly into an overhead folded position, a vertical trackway at each side of the door opening, guide supports projecting into said trackway from the lateral edges of the door sections, guides carried by said supports and movable in said trackway, a head structure communicating at its lower end with the upper end of the vertical trackway and including at its upper end a pair of superposed pockets slightly oifset laterally from the trackway and communicating therewith, an upwardly and rearwardly directed track portion carried by the head structure and forming an extension of the vertical trackway, said last mentioned extension being operatively associated with alternate guides in the folding of the door sections and to secure the seating of the other alternate guides in said pockets, a pivoted track member pivotally supported near the upper, end of said track extension and arranged for engagement by alternate guides and upon opposite sides, means cooperating with the door sections for facilitating the breaking thereof into folded relation in the upward movement of the sections, a pulley associated with said cable and in overhead relation with respect to the door when closed and laterally offset from the trackway, and means swivably supporting said pulley for the purpose set forth.

28. In a folding door structure, the combination of a plurality of horizontally foldable door sections hingedly connected together and arranged for folding and movable upwardly into an overhead folded position, the hingedly connected pairs of doors being initially movable upwardly in substantially the same plane, a vertical trackway at each side of the door opening, guide supports projecting into said trackway and on the ends of certain door sections, guides carried by said supports and movable in said trackway, counterbalancing means for said door sections, a single cable at each side of the door associated with the counterbalancing means and the door sections and alternately positioned forwardly and rearwardly of successive guide supports for the purpose set forth, a head structure communicating at its lower end with the upper end of the vertical trackway and including at its upper end a pair of superposed pockets slightly offset laterally from the trackway and communicating therewith, an upwardly and rearwardly directed track portion carried by the head structure and forming an extension of the vertical trackway, said last mentioned extension being operatively associated with alternate guides in the folding of the door sections and to secure the seating of the other alternate guides in said pockets, means cooperating with the door sectionsv for facilitating the breaking thereof into folded relation in the upward movement of the sections, and a pulley associated with said cable and in overhead relation with respect to the door when closed and laterally olfset from the trackway, and means swivably supporting said pulley for the purpose set forth.

29. In a folding door structure, the combination of a plurality of horizontally foldable door sections hingedly connected together and arranged for folding and movable upwardly into an overhead folded position, the hingedly connected pairs of doors being initially movable upwardly in substantially the same piane. a vertical trackway at each side of the door opening, guide supports projecting into said trackway and on the ends of certain door sections, guides carried by said supports and movable' in said trackway, counterbalancing means for said door sections, a single cable at each side of the door associated with the counterbalancing means and the door sections and alternately positioned forwardly and rearwardly of successive guide supports for the purpose set forth, a head structure communicatl ing at its lower end lwith the upper end of the vertical trackway and including at its upper end a pair of superposed pockets slightly offset from the trackway and communicating therewith, an up- Wardly and rearwardly directed track portion carried by the head structure and forming an extension of the vertical trackway, said last mentioned extension being operatively associated sections and to secure the seating of the other alternate guides in said pockets, a pivoted track member pivotally supported near the upper end of said track extension and arranged for engagement by alternate guides upon opposite sides,

vwith alternate guides in the folding of the door zo means cooperating with the door sections for