BI-FOLD DOOR LATCH ASSEMBLY AND FLOOR ANCHOR ASSEMBLY

Abstract

A bi-fold door is opened with a lift assembly having a plurality of straps attached to power driven lift drums. A latch assembly retains the closed bi-fold door secure to side columns of a building. The latch assembly has a latch strap attached to a latch drum that accommodates the latch strap to hold the closed bi-fold door in contact with the side columns of the building. A floor anchor assembly anchors the bottom of the closed bi-fold door to the floor below the closed bi-fold door to stabilize and inhibit bending and deformation of the bi-fold door frame.

Claims

1. An apparatus for opening and closing a door opening with a bi-fold door mounted on a structure having the door opening and a floor below the door opening, the bi-fold door having an upper panel, a lower panel, and hinges connecting the upper panel and the lower panel to allow the upper and lower panels to move from a vertically aligned closed latched position to a folded side-by-side open position and anchored to the floor when the bi-fold door is in the closed latch position comprising: door lift devices operable to selectively open and close the bi-fold door, door latch assemblies operable to latch the bi-fold door secure to the structure when the bi-fold door is in the closed position, a floor anchor assembly operable to anchor the closed bi-fold door to the floor, a reversible power unit connected to the door lift devices, the door latch assemblies and floor anchor assembly for operating the door lift devices, the door latch assemblies and the floor latch assembly whereby the door lift devices are operable to open and close the bi-fold door, the door latch assemblies are operable to latch the closed bi-fold door secure to the structure, and the floor latch assembly anchors the closed bi-fold door to the floor below the door opening, a drive shaft connected to the power unit, each of the door lift devices having a door lift drum secured to the drive shaft, a first elongated flexible strap having a first end and a second end, the first end being connected to the door lift drum whereby the power unit rotates the drive shaft and door lift drum to wind the first strap in overlapping relation on the door lift drum to move the bi-fold door to an open position and unwind the first strap off the door lift drum to allow the bi-fold door to move to the closed position, a first anchor member mounted on one panel connected to the second end of the first strap, each door latch assembly having a door latch drum secured to the drive shaft, a second elongated flexible strap having a first end and a second end, the first end of the second strap being connected to the door latch drum whereby the power unit rotates the drive shaft and door latch drum to wind the second strap in overlapping relation opposite from the overlapping relation of the first strap on the door lift drum and unwind the second strap off the door latch drum, a second anchor member mounted on a structure of the door opening, said second end of the second strap being connected to the second anchor member whereby the power unit rotates the drive shaft, the door lift drum and the door latch drum to wind the first strap on the door lift drum and unwind the second strap off the door latch drum to open the bi-fold door and the power unit rotates the drive shaft, door lift drum and the door latch drum to unwind the first strap off the door lift drum and wind the second strap on the door latch drum to close the bi-fold door and latch the bi-fold door secure to the structure, said floor anchor assembly having an anchor drum secured to the drive shaft, an anchor rod selectively movable between an anchor position on the floor below the door opening and an unanchored position relative to the floor below the door opening, an anchor member movable between first and second positions, a third elongated flexible strap connected to the anchor rod and anchor member, a fourth elongated flexible strap having a first end connected to the anchor drum and a second end connected to the anchor member whereby the power unit rotates the drive shaft and anchor drum to wind the fourth strap in overlapping relation on the anchor drum thereby moving the anchor member and third strap and anchor rod from the anchor position on the floor below the door opening to an unanchored position relative to the floor below the door opening.

2. The apparatus of claim 1 wherein: the second anchor member includes a roller assembly mounted on the structure adjacent the bi-fold door, the second strap extending from the door latch drum to the roller assembly and around the roller assembly.

3. The apparatus of claim 1 including: a device operable to bias the second strap to maintain tension on the second strap during opening and closing of the bi-fold door.

4. The apparatus of claim 1 wherein: the floor anchor assembly includes: a housing mounted on the bi-fold door, support members connected to the housing for holding the anchor rod and allowing the anchor rod to move between a floor anchor position and a floor unanchor position, and a biasing member for biasing the anchor rod to the floor anchor position.

5. The apparatus of claim 4 wherein: the support members comprise a first support member and a second support member spaced from the first support member, said anchor rod having a rod portion located between said spaced first and second support members, said biasing member comprising a coil spring surrounding the rod portion of the anchor rod to bias the anchor rod to the floor anchor position.

6. The apparatus of claim 1 wherein: the floor below the door opening includes a hole with an open upper end aligned with the anchor rod, and said anchor rod having a lower end located in the hole when the anchor rod is in the anchor position.

7. The apparatus of claim 1 including: a first ratchet device connected to the third strap and anchor member operable to adjust the working length of the third strap between the anchor member and anchor rod, and a second ratchet device connected to the fourth strap and anchor member operable to adjust the working length of the fourth strap between the anchor member and anchor drum.

8. A combination of a door and apparatus for opening, closing a door opening, latching the door secure to a structure providing the door opening and anchoring the door to the floor below the door opening comprising: a bi-fold door adapted to be hinged to a structure having a header located over the door opening, the bi-fold door having an upper panel, a lower panel and hinges pivotally connecting the upper and lower panels to allow the panels to move from an aligned closed latched position to a folded generally side-by-side open position, door lift devices operable to selectively move the bi-fold door to open and close the door opening with the bi-fold door, door latch assemblies operable to retain the bi-fold door secured to the structure when the bi-fold door is in a closed latched position, a floor anchor assembly operable to anchor the bi-fold door to the floor below the door opening, a reversible power unit connected to the door lift devices, the door latch assemblies and floor anchor assembly for operating the door lift devices and the door latch assemblies and floor anchor assembly whereby the door lift devices open and close the bi-fold door and the door latch assemblies latch the closed bi-fold door secured to the structure and the floor anchor assembly anchors the bi-fold door to the floor below the door opening, each of the door lift devices having an elongated flexible first strap having a first end and a second end, a rotatable first drum attached to the first end of the first strap operably connected to the power unit whereby on rotation of the first drum the first strap winds in overlapping relation around the first drum, a first anchor member mounted on one of the panels connected to the second end of the first strap, each of the door latch assemblies having an elongated flexible second strap having a first end and a second end, a second rotatable drum attached to the first end of the second strap operatively connected to the power unit whereby on rotation of the second drum the second strap winds in overlapping relation around the second drum in a direction opposite from the overlapping relation of the first strap and the first drum, a second anchor member connected to structure adjacent the door opening and the second end of the second strap whereby when the power unit rotates the first and second rotatable drums to wind the first strap on the first drum and unwind the second strap off the second drum the upper and lower panels pivot relative to each other to a side-by-side relationship to open the bi-fold door and when the power unit rotates the first and second drums to unwind the first strap off the first drum and wind the second strap on the second drum the upper and lower panels pivot relative to each other to aligned relationship to close the hi-fold door and latch the bi-fold door secure to the structure adjacent the door opening, said floor anchor assembly having an anchor drum operably connected to the power unit, an anchor selectively movable between a first position for holding the bi-fold door in the bi-fold door closed position on the floor below the door opening and a second position releasing the anchor from holding the bi-fold door on the floor below the door opening, an anchor member mounted on the bi-fold door movable between first and second positions, a flexible third strap connected to the anchor and anchor member, and a flexible fourth strap connected to the anchor drum and anchor member whereby when the power unit rotates the anchor drum to wind the fourth strap on the anchor drum, the anchor member is moved from the first position to the second position thereby moving the third strap and anchor from the anchor position to the unanchor position.

9. The combination of claim 8 wherein: the power unit includes a drive shaft, the first and second drums being connected to the drive shaft whereby upon rotation of the drive shaft in one direction the first strap winds in overlapping relation around the first drum and the second strap unwinds off the second drum thereby moving the bi-fold door from a closed latched position to an open position and upon rotation of the drive shaft in a direction opposite the one direction the first strap unwinds off the first drum and the second strap winds in overlapping direction around the second drum whereby the bi-fold door moves from the open position to the closed latched position, said anchor drum being connected to the drive shaft whereby on rotation of the drive shaft in said one direction the fourth strap winds in overlapping relation around the anchor drum thereby moving the anchor member to the second position and moving the third strap and anchor to release the anchor from holding the bi-fold door on the floor below the door opening.

10. The combination of claim 8 wherein: the floor anchor assembly includes a housing mounted on the lower panel of the bi-fold door, a plurality of support members connected to the housing for holding the anchor and allowing the anchor to move between the first position for holding the bi-fold door in the bi-fold door closed position on the floor below the door opening and the second position releasing the anchor from holding the bi-fold door on the floor below the door opening, and a biasing member for biasing the anchor to the first position for holding the bi-fold door in the bi-fold door closed position on the floor below the door opening.

11. The combination of claim 10 wherein: the anchor is an elongated rod movably mounted on the plurality of support members for movement between the first and second positions.

12. The combination of claim 10 wherein: the anchor is an elongated rod movably mounted on the plurality of support members for movement between the first and second positions, and said biasing member comprises a coil spring surrounding the rod for biasing the rod to the first position.

13. The combination of claim 8 wherein: the anchor member is a motion transmission mechanism movably mounted on the bi-fold door between said first and second positions, said third strap being connected to the motion transmission mechanism and anchor, said fourth strap being connected to the anchor drum and motion transmission mechanism whereby when the power unit rotates the anchor drum to wind the fourth strap on the anchor drum, the motion transmission mechanism is moved from the first position to the second position the third strap is moved to release the anchor from holding the bi-fold door on the floor below the door opening.

14. An apparatus for opening and closing an opening in a structure with a bi-fold door mounted on the structure for movement between a closed position and an open position and anchored to the floor below the opening when the bi-fold door is in the closed position comprising: a door lift assembly operable to selectively open and close the bi-fold door, a door latch assembly operable to latch the bi-fold door secured to the structure when the bi-fold door is in the closed position, a floor anchor assembly operable to anchor the closed bi-fold door to the floor below the closed bi-fold door, and a reversible power transmission assembly operatively connected to the door lift assembly, the door latch assembly and the floor anchor assembly to operate the door lift assembly to selectively open and close the bi-fold door, to operate the door latch assembly to secure the bi-fold door to the structure when the bi-fold door is in the closed position and to operate the floor anchor assembly to anchor and release the anchor of the bi-fold door to and from the floor below the opening in the structure when the bi-fold door is in the closed position.

15. The apparatus of claim 14 wherein: the floor anchor assembly comprises: an anchor operably connected to the power unit, a housing adapted to be mounted on the bi-fold door, at least one support member connected to the housing for holding the anchor and allowing the anchor to move between a floor anchor position and a floor unanchor position, and a biasing member operatively connected to the anchor for biasing the anchor to the floor anchor position thereby anchoring the closed bi-fold door to the floor below the opening in the structure.

16. The apparatus of claim 15 wherein: the anchor is an elongated rod movably mounted on the at least one support member for movement between the floor anchor position and the floor unanchor position, and said biasing member comprises a coil spring surrounding the rod operable to bias the rod to the floor anchor position.

17. The apparatus of claim 14 wherein: the floor anchor assembly comprises: an anchor rod, a housing adapted to be mounted on the bi-fold door, a first support member connected to the housing, a second support member spaced from the first support member connected to the housing, said anchor rod being movably mounted on the first and second support members for movement to a floor anchor position and from the floor anchor position to a floor unachor position, a collar secured to the anchor rod between the first and second support members, a coil spring surrounding the anchor rod and engageable with the first support members and the collars for biasing the anchor rod to the floor below the opening in the structure.

18. The apparatus of claim 14 wherein: the reversible power transmission assembly includes: a drive shaft, a motor operable to rotate the drive shaft, an anchor drum mounted on the drive shaft for rotation with the drive shaft, and a strap secured to the anchor drum and operatively connected to the anchor, said strap being wound on the anchor drum during rotation of the anchor drum to move the anchor from the anchor position on the floor to the unanchor position.

19. The apparatus of claim 14 wherein: the reversible power transmission assembly includes: a motion transmission mechanism having a first member mountable on the bi-fold door and a second member hinged to the first member for movement between first and second positions, a first strap connected to the anchor rod and second member of the motion transmission mechanism, a drive shaft adapted to be mounted on the bi-fold door, a power device for rotating the drive shaft, an anchor drum mounted on the drive shaft for rotation with the drive shaft when the power device rotates the drive shaft, and a second strap connected to the second member of the motion transmission mechanism and the anchor drum whereby on rotation of the anchor drum the second strap winds onto the anchor drum moving the second member of the motion transmission mechanism from the first position to the second position and moving the first strap and anchor rod from the anchor position below the opening to the structure to an unanchor position.

20. The apparatus of claim 19 including: a first ratchet device connected to the first strap and second member of the motion transmission mechanism operable to adjust the working length of the first strap between the second member of the motion transmission mechanism and anchor rod, and a second ratchet device connected to the second strap and second member of the motion transmission mechanism operable to adjust the working length of the second strap between the second member of the motion transmission mechanism and the anchor drum.

21. A floor anchor assembly for holding a door on a floor of a doorway of a building comprising: a housing, a rod, at least one member secured to the housing for holding the rod and allowing the rod to be moved between a first position for holding the door on the floor of a doorway and a second position for releasing the holding of the door on the floor of a doorway, a biasing member for biasing the rod to the first position for holding the rod on the floor of the doorway, and a lift assembly operatively connected to the rod for moving the rod from the first position to the second position to release the holding of the rod on the floor of the doorway.

22. The floor anchor assembly of claim 21 wherein: the at least one member comprises a pair of spaced members secured to the housing, said members accommodating the rod for movement between the first and second positions, said rod having a rod portion located between the spaced members, and said biasing member includes a coil spring surrounding the rod portion for biasing the rod of the first position for anchoring the rod to the floor of the doorway.

23. The floor anchor assembly of claim 21 wherein: the lift assembly includes a first member movable between first and second position, a second member connected to the first member and the rod, a third member connected to the first member, and a fourth member connected to third member operable to move the third member and first and second members from the first position to the second position whereby the rod moves from the first position to the second position to release the anchoring of the rod from the floor of the doorway.

24. The floor latch assembly of claim 23 wherein: the second member is a first strap and the third member is a second strap.

25. The floor anchor assembly of claim 23 including: a first ratchet device connected to the first member and to the first strap operable to adjust the working length of the first strap, and a second ratchet device connected to the first member and to the second strap operable to adjust the working length of the second strap.

26. The floor anchor assembly of claim 21 wherein: the lift assembly includes a yoke connected to the rod, a first strap attached to the yoke, a motion transmission mechanism having a member movable between first and second positions, said first strap being connected to the member of the motion transmission mechanism, a second strap connected to the member of the motion transmission mechanism, and an apparatus connected to the second strap operable to move the second strap and move the member of the motion transmission mechanism from the first position to the second position whereby the first strap moves, the rod to release the holding of the rod on the floor of the doorway.

27. The floor anchor assembly of claim 26 including: a first ratchet device connected to the first strap and member of the motion transmission mechanism operable to adjust the working length of the first strap between the yoke and member of the motion transmission mechanism, and a second ratchet device connected to the second strap and member of the motion transmission mechanism to adjust the working length of the second strap between the apparatus and member of the motion transmission mechanism.

Description

DESCRIPTION OF THE DRAWING

[0011] FIG. 1 is a perspective view of a bi-fold door closing a doorway of a building with a door lift assembly, a door latch assembly and floor anchor assembly;

[0012] FIG. 2 is a perspective view of the bi-fold door of FIG. 1 in a partly open position;

[0013] FIG. 3 is an inside elevational view of the bi-fold door of FIG. 1;

[0014] FIG. 4 is a perspective sectional view taken along line 4-4 of FIG. 3;

[0015] FIG. 5 is an enlarged foreshortened sectional view taken along line 5-5 of FIG. 4;

[0016] FIG. 6 is an end elevational view of the strap anchor for the door lift assembly;

[0017] FIG. 7 is an enlarged sectional view of the lift drum accommodating a strap taken along the line 7-7 of FIG. 4;

[0018] FIG. 8 is an enlarged sectional view of a section of the bi-fold door with a strap door lift assembly and a latch assembly;

[0019] FIG. 9 is a perspective sectional view taken along line 9-9 of FIG. 3;

[0020] FIG. 10 is a partly sectioned front elevational view of a latch assembly for moving and holding the bi-fold door in the closed position;

[0021] FIG. 11 is a sectional view taken along line 11-11 of FIG. 10;

[0022] FIG. 12 is a partly sectioned side elevational view of the upper end of the latch assembly shown in FIGS. 10 and 11;

[0023] FIG. 13 is a sectional view taken along line 13-13 of FIG. 12;

[0024] FIG. 14 is a perspective view of the latch assembly strap ratchet and bracket assembly;

[0025] FIG. 15 is a perspective view of the strap lift drum and strap latch drum connected to the drive shaft of the door lift assembly;

[0026] FIG. 16 is a side elevational view showing the bi-fold door in a partly open position;

[0027] FIG. 17 is an enlarged sectional view taken along line 17-17 of FIG. 3 showing the anchor pin of the floor anchor assembly in a lock position;

[0028] FIG. 18 is an enlarged sectional view taken along line 18-18 of FIG. 3;

[0029] FIG. 19 is an enlarged sectional view taken along line 19-19 of FIG. 3;

[0030] FIG. 20 is an enlarged sectional view taken along line 20-20 of FIG. 3;

[0031] FIG. 21 is a perspective view of the double strap anchor assembly;

[0032] FIG. 22 is a bottom perspective view of the double strap anchor assembly of FIG. 20;

[0033] FIG. 23 is a perspective view of the door anchor strap ratchet and strap of the double strap anchor assembly;

[0034] FIG. 24 is a perspective view of the door lift strap ratchet and strap of the double strap anchor assembly;

[0035] FIG. 25 is an enlarged perspective view of the floor anchor assembly shown in FIGS. 3 and 17;

[0036] FIG. 26 is a front elevational view of FIG. 24;

[0037] FIG. 27 is a left side elevational view of FIG. 25;

[0038] FIG. 28 is a right side elevational view of FIG. 25;

[0039] FIG. 29 is a sectional view taken along line 29-29 of FIG. 26;

[0040] FIG. 30 is a top plan view of FIG. 26;

[0041] FIG. 31 is a bottom plan view of FIG. 26;

[0042] FIG. 32 is a sectional view taken along line 32-32 of FIG. 25;

[0043] FIG. 33 is a sectional view taken along line 33-33 of FIG. 25;

[0044] FIG. 34 is a back elevational view of FIG. 25;

[0045] FIG. 35 is a sectional view corresponding to FIG. 17 showing the anchor rod in an unlock position;

[0046] FIG. 36 is an enlarged front elevational view of the floor anchor assembly of FIG. 35;

[0047] FIG. 37 is a perspective view of the floor anchor assembly with the anchor rod in the floor lock position and the anchor rod lift assembly for the floor anchor assembly; and

[0048] FIG. 38 is a perspective view of the floor anchor assembly with the anchor rod in the floor unanchor or release position and the rod lift assembly for the floor anchor assembly.

DESCRIPTION OF THE BI-FOLD DOOR WITH LIFT MECHANISMS, LATCH ASSEMBLIES AND A FLOOR ANCHOR ASSEMBLY

[0049] In the following detailed description of the bi-fold door equipped with latch assemblies and floor anchor assembly, reference is made to the accompanying drawing that form a part hereof, and in which are shown, by way of illustration, specific embodiment in which the invention may be practiced. It is to be understood that other embodiments may be utilized and structure changes may be made or other method steps and sequence thereof may be used without departing from the scope of the present invention. The latch assembly and floor anchor assembly are herein described as used in building environment. The bi-fold door is described as having a single latch assembly and a single floor anchor assembly. Latch assemblies are mounted on opposite sides of the bi-fold door to secure both sides of the bi-fold door to the side columns of the structure. A plurality of floor anchor assemblies can be mounted on the bi-fold door to anchor the closed bi-fold door to the floor below the closed bi-fold door. The latch assembly and floor anchor assembly can have uses in other environments when securing doors used to close an opening is desired.

[0050] A building 20, shown in FIGS. 1 and 2, has an opening or doorway 21 that is open and closed with a bi-fold door 22. Examples of building 20 include aviation hangers, automotive shops, farm shops, commercial buildings, warehouses and commercial plants. Building 20 has a horizontal header 23, shown in FIG. 3, attached to upright end columns 24 and 26 located around doorway 21 open to the interior of building 20. Bi-fold door 22 has an upper panel 27 and a lower panel 28 movable between upright aligned positions to close doorway 21. Panels 27 and 28 when located in the upright closed positions have large flat outside surfaces that are subjected to moving air or wind forces, shown by arrows 25. These wind forces are extreme in severe weather conditions, such as torrential rain, tornados and hurricanes. The latch assemblies in combination with one or more floor anchor assemblies provide the closed door with stability and inhibits bending and deformation of the door frame when subjected to wind forces. Panels 27 and 28 are moved with lift assemblies to folded horizontal positions to open doorway 21. Examples of bi-fold doors are disclosed in U.S. Pat. Nos. 4,637,446; 5,168,914; 6,199,617 and 6,866,080.

[0051] Bi-fold door 22 has a metal frame 29 supporting upper and lower panels 27 and 28. Upper panel frame has left and right upright side members 31 and 32 and a middle member 33 located between members 31 and 32. Top and bottom horizontal members 38 and 39 and upright middle members 41, 42, 43 and 44 are joined to members 38 and 39. Bottom panel 28 has top and bottom horizontal members 34 and 36 joined to end members 31 and 32. A horizontal frame member 35 located below frame member 37 is secured to frame members 31 and 32 and upright frame members 46, 47, 48 and 49. Frame members are elongated tubular beams welded to provide one-piece frames for panels 27 and 28. Sheathing 51 secured to frame 29 covers the outside of frame 29. A plurality of hinges 52 connected to frame members 39 and 34 pivotally join panels 27 and 28 for movement between an upright aligned closed position and a horizontal folded open position. A plurality of hinges 53 connected to top frame member 38 and header 23 pivotally mount door 22 on header 23 for swinging movement between an upright closed position and a generally horizontal folded open position.

[0052] A door lift assembly 54 functions to lift door 22 from the upright closed position to the generally horizontal folded open position. Lift assembly 54 also retains door 22 in the open position. When lift assembly 54 releases door 22 the weight of door 22 returns door 22 to a nearly closed position. Automatic latch assemblies 94 and 96 hereinafter described move panels 27 and 28 in upright aligned positions closing doorway 21 and retaining opposite sides of panels 27 and 28 in engagement with columns 24 and 26. As shown in FIG. 3, door lift assembly 54 comprises a horizontal shaft 56 rotatably mounted on supports 57, 58, 59 and 60 secured to bottom member 36 of the lower panel frame. Supports 57, 58, 59 and 60 have bearings accommodating shaft 56 for rotation about a generally horizontal axis. A plurality of elongated flexible members, such as webs or straps 61, 62, 63 and 64 operatively connect shaft 56 to upper panel 27 whereby rotation of shaft 56 in one direction moves bi-fold door 22 from the closed position to the open position and releases the automatic latch assemblies 94 and 96 and rotation of shaft 56 in an opposite direction to the one direction allows bi-fold door 22 to move from the open position to the closed position and operating automatic latch assemblies 94 and 96 to retain panels 27 and 28 in upright aligned positions in secure engagement with columns 24 and 26 of building 20. As shown in FIG. 4, member 61 is an elongated flexible flat web or strap, such as a nylon or polyester web. The upper section of member 61 is trained over a support 66 secured to upper frame member 38 and terminating on an anchor member 67 secured to frame member 33. As shown in FIG. 5, support 66 has an inverted U-shaped bracket 68 secured with welds to the bottom of frame member 38. A roller or sleeve 69 is rotatably mounted on a bolt 71 attached to bracket 68. Strap 61 trained over roller 69 can move with roller 69 thereby reducing wear and strain on member 61. Ratchet anchor 67 has a U-shaped bracket 72 rotatably supporting a sleeve 73. Member 61 is wrapped around and secured to sleeve 73 to connect member 61 to sleeve 73 thereby anchoring member 61 to door frame 29. As shown in FIG. 6, the slack or tension of strap 61 is adjusted with a ratchet ring 74 secured to sleeve 73. A holding pawl 76 is held with a cotter pin 77 in engagement with the teeth on ring 74. Other devices can be used to adjust the slack or tension on strap 61. Flexible straps 62, 63, 64 are trained over rollers operatively connected to frame member 39 and anchored to frame member 33 according to member 61 as shown in FIGS. 4, 5 and 6. The lower end of member 61 is connected to lift drum 78 secured to shaft 56. As shown in FIG. 7, disks 79 and 81 attached to opposite ends of drum 78 maintain member 61 in wrapping relation around drum 78 during winding of strap 61 on drum 78 and unwinding of member 61 from drum 78. As shown in FIGS. 3 and 9, a reversible electric motor 82 drives a power transmission 83 operable to transmit power through chain drives 84 and 86 coupled to sprockets 87 and 88 to shaft 56 whereby shaft 56 is selectively rotated in opposite directions to move bi-fold door 22 to a folded open position and allow door 22 to move to a closed position. Shaft 56 is rotated in a counterclockwise direction, shown by arrow 89, to wind strap 61 around drum 78 to move door 22 to the open folded position. Lift drums 91, 92 and 93, shown in FIG. 3, secured to shaft 56 accommodates flexible straps 62, 63 and 64 and concurrently wind and unwind flexible straps 62, 63 and 64 on drums 91, 92 and 93 as flexible strap 61 winds and unwinds on drum 78. Limit switches (not shown) associated with electric motor 82 and transmission 83 control the duration or timing of the operation of electric motor 82.

[0053] Latch assemblies 94 and 96 mounted on opposite ends of frame 29 are operable to move panels 27 and 28 in upright or vertically aligned positions and retain panels 27 and 28 in secure engagement with columns 24 and 26 when door 22 is in the closed position. As shown in FIGS. 8, 10 and 11, latch assembly 94 secured to door fame 29 adjacent column 24 comprises an upright U-shaped frame 97. Frame 97 is fastened with welds to frame member 38 and adjacent frame members. Other types of fasteners can be used to attach frame 97 to door frame 29. As shown in FIGS. 12 and 13, a pair of horizontal rollers 98 and 99 are mounted on the upper end of frame 97. Rollers 98 and 99 are parallel and laterally spaced apart to accommodate a roller bracket assembly 101. Roller bracket assembly 101 has upright flat side members 102 and 103 connected to an upper pin or rod 104 and a lower pin or rod 106. A latch drum 109 located below frame 97 is rotatably mounted on support 111 secured to door frame member 36. Shaft 56 is drivably connected to latch drum 109 to rotate latch drum 109 when driven by electric motor 82. Rotation of shaft 56 concurrently rotates lift drums 78, 91, 92 and 93 and latch drums 109 and 112 to move bi-fold door 22 to the upright closed position and retain bi-fold door 22 in the upright closed position. A latch strap 113 attached to latch drum 109 extends upward into U-shaped frame 97 between a roller 114 and back wall of frame 97. The upper section of strap 113 extends horizontally over rollers 98 and 99 to a strap anchor 116. As shown in FIG. 14, anchor 116 has a bracket 117 secured with fasteners 118 to column 24. A U-shaped support 119 secured to bracket 117 rotatably accommodates a sleeve 121. Strap 113 is secured to sleeve 121. Strap 113 is wound around sleeve 121 to adjust the effective length of strap 113 to retain bi-fold door 22 in the upright closed position. A ratchet wheel 122 secured to sleeve 121 is used with a tool (not shown) to rotate sleeve 121 to wind strap 113 on sleeve 121. A pin 123 fixed to support 119 engages ratchet wheel 122 to hold ratchet wheel 122 and sleeve 121 in an adjusted position with strap 113 wound on sleeve 121. Returning to FIGS. 10 and 11, a tension spring 124 has a lower end connected to a bolt 126 extended through holes 127 in latch frame 97. Latch frame 97 has a plurality of vertically arranged holes 127 accommodating bolt 126 for adjusting the biasing force of spring 124 on strap 113, shown by arrow 128 in FIG. 12. The upper end of spring 124 is connected to pin 106 of roller bracket assembly 101. Pin 104 located on top of strap 113 between rollers 98 and 99 applies the biasing force of spring 124 to pull strap 113 down between rollers 98 and 99 to take up slack of strap 113 and maintain the tension on strap 113 during the opening and closing of bi-fold door 22.

[0054] Latch assembly 96 mounted on the right end of door 22, as shown in FIG. 3, has the same structure and operation as latch assembly 94. Shaft 56 is drivably connected to latch drum 112 to rotate latch drum 112 whereby strap 128 is wound on and unwound from latch drum 112 during the opening and closing of bi-fold door 22 and the latching and unlatching functions of latch assembly 96. As shown in FIG. 15, when shaft 56 is rotated counterclockwise, shown by arrow 89, strap 61 is wound on lift drum 78. Straps 62, 63 and 64 are also wound on drums 91, 92 and 93. The combined straps 61, 62, 63 an 64 move down, shown by arrow 129, thereby moving bi-fold door 22 from the closed position to the folded open position. During counterclockwise rotation of shaft 56 latch drum 109 unwinds strap 113 from latch drum 109 whereby strap 113 moves upward releasing the horizontal force holding bi-fold door 22 in the closed position and allowing the bi-fold door to move upwardly to the open position, as shown by arrows 132 in FIG. 16. Strap 113 rides on roller 132 on the bottom of frame member 36 during movement of bi-fold door 22 between open and closed positions. Spring 124 connected to roller bracket assembly 101 maintains a continuous biasing force on strap 113 during the opening and closing of bi-fold door 22. Shaft 56 is rotated in a clockwise direction by reversing the drive of electric motor 82. Straps 61, 62, 63 and 64 unwind from lift drums 78, 91, 92 and 93 allowing bi-fold door 22 to unfold from the open position to an upright closed position. The weight of bi-fold door 22 causes bi-fold door 22 to move down as straps 61-64 unwind from their respective lift drums. Strap 113 as it winds onto latch drum 109 pulls bi-fold door 22 to an upright closed position against columns 24 and 26. When bi-fold door 22 is in the closed position, spring 124 acting on strap 113 biases bi-fold door 22 against column 24 and maintains bi-fold door 22 in the upright closed position.

[0055] A floor anchor assembly 133, shown in FIGS. 3 and 17, secured to door frame 29, holds the bottom of door 22 in its closed position in an anchor or fixed position on the floor or support below the door. A plurality of floor anchor assemblies can be secured to door frame 29 to hold bi-fold door 22 on the floor below the closed bi-fold door 22. Floor anchor assembly 133 has a body or housing 134 mounted on door frame members 35 and 36. Housing 134 is a metal U-shaped member having a front wall 136 joined to side walls 137 and 138. Front wall 136 has a rectangular opening 139 and top and bottom vertical slots 141 and 142 open to opening 139. As shown in FIGS. 27 and 28, side wall 137 has top and bottom rectangular recesses 143 and 144 aligned with top and bottom rectangular recesses 146 and 147 in side wall 138. Housing 134 is mounted on frame members 35 and 36; shown in FIG. 17, with frame member 35 located in top recesses 143 and 146 and frame member 36 located in bottom recesses 144 and 147. Welds secure side walls 137 and 138 to frame members 35 and 36.

[0056] As shown in FIG. 29, an upright pin or rod 148 extends through sleeves 151 and 152. Rod 148 is an anchor that operates to retain the bi-fold door 22 in a fixed or stationery position relative to the floor below bi-fold door 22. Rod 148 has a lower end 149 that projects downward from the lower end of housing 134. Sleeve 151 has an upright rib 153 located in slot 141. Sleeve 152 has an upright rib 154 located in slot 142. Welds secure ribs 153 and 154 to front wall 136 of housing 134 to secure sleeves 151 and 152 to housing 134. Sleeves 151 and 152 are support members for rod 148 and allow rod 148 to move between up and down positions relative to housing 134. A coil spring 156, shown in FIGS. 25, 26, 29 and 34, is trained around rod 148 between sleeves 151 and 152. The upper end of spring 156 engages sleeve 141. The lower end of spring 156 engages a collar 157 located around rod 148. A set screw 158 secures collar 157 to rod 148. Spring 156 is a biasing member that retains rod 148 in its down floor anchor position. Collar 157, shown in FIG. 29, contacts sleeve 152 whereby sleeve 152 functions as a stop to limit downward movement of rod 148. The location of collar 157 along the length of rod 148 is adjustable to vary the down floor anchor position of rod end 149.

[0057] Returning to FIGS. 17 and 26, the lower end 149 of rod 158 is located in a cavity or hole 159 in floor 161 located below the closed door 22. An upright metal tube 162 embedded or fixed into floor 161 surrounds hole 159. Other structures can be used to lock rod 158 to the floor 161. Floor 161 is a stationary support comprising concrete, asphalt, wood and like materials. When rod end 149 is located in hole 159 door 22 is laterally stabilized and door frame 29 is inhibited from bending and deforming when subjected to wind and load forces.

[0058] Rod 148 is moved upward to withdraw rod end 149 from hole 159 in floor 161 to allow door 22 to be moved from the closed position to the open position. An anchor release assembly 163 operatively connected to rod 148 and shaft 56 moves rod 148 to an unlock position out of hole 159 in response to operation of door lift mechanism 54. Assembly 163 comprises an inverted U-shaped member or yoke 164. As shown in FIG. 34 yoke 164 has a pair of legs 166 and 167 that extend downward into housing 134 adjacent opposite sides of sleeve 151. The upper ends of legs 166 and 167 are joined to a body 168 having three spaced horizontal openings or slots 169, 170 and 171. The upper end of rod 148 is secured with welds to body 168 whereby rod 148 and yoke 164 concurrently move relative to housing 134 to floor anchor and unanchor positions. A flexible flat strap 172 connects body 168 of yoke 164 to a motion transmission mechanism 173. Strap 172 is threaded through slots 169, 170 and 171, as shown in FIGS. 17, 25 and 29 to secure strap 172 to body 168 of yoke 164.

[0059] Motion transmission mechanism 173 secured to frame member 33 comprises a first plate 174 having a top section attached with a weld to frame member 33. A second plate 176 located below first plate 174 is pivotally connected with a hinge 177 to first plate 174 for movement between an open first position, shown in FIGS. 17, 18 and 21, and a closed position, shown in FIGS. 22 and 35. A first ratchet strap anchor 178 is mounted on second plate 176. Strap 172 extends upward under hinge pin 179 to ratchet strap anchor 178. Strap anchor 178, shown in FIGS. 22 and 23, comprises a U-shaped member 181 secured to second plate 176. A sleeve 182 with an elongated slot 183 is rotatably mounted on U-shaped member 181. Strap 172 has an end extended into slot 183 to attach strap 172 to sleeve 182 whereby strap 172 is wrapped around sleeve 182 to adjust the effective working length of strap 172 between yoke 164 and first ratchet strap anchor 178. A ratchet wheel 184 secured to an end of sleeve 182 cooperates with a pawl 186 to retain sleeve 182 and strap 172 in adjusted positions. A tool (not shown) is used to turn ratchet wheel 184 to wind strap 172 onto sleeve 182 to adjust the effective working length of strap 172. A cotter pin 187 extended through a hole in the U-shaped member 181 contracts pawl 186 to hold pawl 186 in locking engagement with ratchet wheel 184 thereby maintaining the effective working length of strap 172 between yoke 164 and first ratchet strap anchor 178. As shown in FIGS. 17 and 18, when motion transmission mechanism 163 is in the open or first position strap 172 do not exert a pulling force on yoke 164 whereby spring 156 biases rod 148 down to locate the lower end 149 of rod 148 in hole 159 in floor 161 whereby floor anchor assembly 133 inhibits lateral and transverse movements of closed door 22 when subjected to moving air, rain and snow forces.

[0060] Returning to FIGS. 22 and 24, a second strap anchor 188 is attached to plate 176 adjacent first strap anchor 178. Second strap anchor 188 have U-shaped member or bracket 189 secured with a weld to plate 176. A sleeve 191 with a slot 192 is rotatably mounted on U-shaped member 189. A lift strap 197 has an end extended through slot 192 to attach strap 197 to sleeve 191 whereby strap 197 is wrapped around sleeve 191. A ratchet wheel 193 secured to an end of sleeve 191 is used to rotate sleeve 191 and retain sleeve 191 and strap 197 in adjusted positions. Strap 197 is adjusted to have an effective working length between motion transmission mechanism 173 and door lift drum 198 secured to shaft 56. A pawl 194 mounted on U-shaped member 189 engages ratchet wheel 193 to retain sleeve 191 and strap 197 in adjusted positions. A tool (not shown) is used to turn ratchet wheel 193 to wind strap 197 onto sleeve 191 to adjust the working length of strap 197. A cotter pin 196 extended through a hole in U-shaped member 189 engages pawl 194 to hold pawl 194 in a locked position on ratchet wheel 193 thereby maintaining the effective working length of strap 197.

[0061] As shown in FIG. 19, an anchor member 199 is attached to door frame member 38 for the upper section of lift strap 197. Anchor member 199 comprises a U-shaped bracket 201 welded to the bottom of frame member 38. Bracket 201 accommodates a horizontal pin 202. A tubular member or sleeve 203 is rotatably located on pin 202. Strap 197 trained over sleeve 202 extends downward to lift drum 198. The lower end of strap 197 is connected to lift drum 198 as shown in FIG. 20. Lift drum 198 is secured to shaft 56.

[0062] In use electric motor 82 operates to transmit power to shaft 56 whereby lift drums 57, 58, 59 and 60 along with lift drum 198 rotate in a first direction to together move door 22 from a closed upright position to a folded open position adjacent header 23. Shaft 56 when rotated in a second direction opposite the first direction allows bi-fold door 22 to move from the open folded position to the closed position and rotates latch drum 109 to wind latch strap 113 on the latch drum 109 whereby latch strap 113 holds the sides of bi-fold door 22 in firm contact or engagement with the adjacent doorway columns.

[0063] As shown in FIGS. 3 and 37, when bi-fold door 22 is in the upright closed position the lower end 149 of rod 148 is located in an anchor position in hole 159 in floor 161. Rod 148 mounted on housing 134 secured to door frame members 35 and 36 inhibits lateral movement of bi-fold door 22 when the lower end 149 of rod is located in hole 159. Rod 148 is moved down shown by arrow 204 to the anchor position by the biasing force of spring 156. Motion transmission mechanism 173 is in a down or first position whereby strap 172 allows rod 148 to be moved by spring 156 to the anchor position. As shown in FIG. 38, drive shaft 56 rotated by the power assembly, motor 82 and power transmission 83, rotates anchor drum 198 to wind strap 197 onto anchor drum 198. Strap 197 as it is wound onto anchor drum 198 moves motion transmission mechanism 173 from the down open position, shown in FIGS. 17 and 37, to the up closed position, shown in FIGS. 35 to 38. The movement of the motion transmission mechanism 173 from the down to up position moves strap 172 upward, shown by arrow 206, thereby moving rod 148 upward out of hole 159 in floor 161 to release anchoring of bi-fold door 22 on floor 161. Motion transmission mechanism 173 in the folded up position functions as an anchor member for the upper end of strap 197. Ratchet 178 mounted on motion transmission mechanism 173 adjusts the working length of strap 172 between yoke 164 and motion transmission mechanism 173. Ratchet 188 mounted on motion transmission mechanism 173 adjacent ratchet 178 adjusts the working length of strap 197 between anchor drum 198 and motion transmission mechanism 173.

[0064] One embodiment of the bi-fold door lift assembly, door latch assembly and floor anchor assembly has been shown and described. It is understood that changes and modifications in the materials, construction and arrangement of the cooperating assemblies may be made without departing from the invention as expressed in the following claims.