Elevator door belt linkage

Abstract: An elevator door operator drive belt (14) is joined in a continuous shape by a linkage (24) which attaches to a door panel (26). The linkage utilizes a separate portion of the belt (50) to form an interlocking fit with each end (46, 48) of the belt. The portion (50) overlaps the end portions (46, 48) and is clamped against them by a clamping plate (30). The linkage attaches to the door panel independently of the interlocking fit via a mounting bracket (32).

Description: This invention relates to an elevator door operator and more particularly but not exclusively to a linkage for connecting a door operator cog belt to itself and to a door panel. It also extends to a drive belt linkage for joining the ends of a drive belt and to a system for connecting a drive belt to a door panel. Some elevator door operating systems consist of a reversible motor, a belt, a speed reducing pulley, a transmission pulley, an idler pulley, and a continuous toothed belt. The motor transmits torque via the belt to the speed reducing pulley. The speed reducing pulley is attached to the transmission pulley. The cog belt, which extends around the transmission and idler pulleys, is driven by the transmission pulley. A portion of the cog belt travels linearly between the transmission pulley and the idler pulley. The linear motion of the cog belt is transmitted to each car door panel by means of a linkage. A known linkage for a toothed belt is disclosed in Patent Abstracts of Japan vol. 7 No. 79 (M-204) (1224) and JP-A-58005554. It is an object of the invention in preferred embodiments at least to provide a cog belt and linkage which is inexpensive and easy to install. It is a further object of the invention in preferred embodiments at least to tension a cog belt independently of the position of the door panels. According to the invention there is provided a linkage according to claim 1. In the preferred embodiment, an elevator door operator drive belt is joined in a continuous shape by a linkage which attaches to a door panel. The linkage utilizes a separate portion of the belt to form a friction fit with each end of the belt. The linkage attaches to the door panel independently of the friction fit. Preferably the belt is formed with teeth or similar formations, whereby an interlocking engagement is obtained between the belt portions. This considerably improves the integrity of the joint. A preferred embodiment of the invention will now be described by way of example, with reference to the accompanying drawings in which: Fig. 1 is a perspective view of a door operating system employing an embodiment of a linkage of the invention; and, Fig. 2 is a perspective view, broken away, of the linkage of Fig. 1. As shown in Fig. 1, a door operating system 10 comprises a reversible motor 12, a belt 22, a speed reducing pulley 16, a transmission pulley 18, an idler pulley 20, and a continuous toothed cog belt 14. A pair of linkages 24 transmit the motion of the belt to a pair of door operating panels 26. Referring to Fig. 2, an expanded view of one of the linkages 24 of Fig. 1 is shown. The linkage comprises a housing 28, a clamping plate 30, a bracket 32 and a pair of threaded bolts 34. The housing has a groove 36 therein having a width that provides a slight interference fit with the width of the belt 14, and a depth that is approximately equal to the cross-sectional thickness of the teeth 38 of the belt. The housing has a pair of threaded openings 40 for mating with the threaded bolts 34. The plate has a pair of holes 42 which align with the threaded openings in the housing. The bracket 32 is L-shaped and has an elongated slot 44 for receiving the bolts. In order to form a closed loop and transmit linear motion to the door panels, cog belt ends 46 and 48 are slid into close proximity in the groove 36. The interference fit in the groove helps maintain the ends of the belt in the housing until the clamping plate 30 is attached thereto. Once the two ends of the belt have been brought together and approximately centered in the groove 36, another piece 50 of the cog belt 14 is cut to approximately the length of housing 28 and is placed in register with both ends of the cog belt 46, 48 such that the teeth 38 of piece 50 mate with the teeth 38 in the cog belt ends 46, 48 thus forming a perfect link between cog belt ends. The clamping plate 30 is then pressed against piece 50. The bolts 34 are then inserted through the holes 42 and threaded into the threaded openings 40 in the housing and tightened. By tightening the clamping plate to the housing, a solid link is achieved due to friction forces between the plate, the housing and the respective cog belt teeth. Furthermore a positive interengagement is obtained between the piece 50 and the cog belt ends 46, 48. The bolts may then be inserted through the slot 44 in the bracket and tightened by means of nuts 52. The threaded holes in the housing also allow the ends of the belt to be joined without having to link the device to the bracket 32, which is connected directly to an elevator door hanger (not shown). By means of the slot 44, the bracket may be finally positioned independently (depending on the length of the slot) of the housing position. As a result, the cog belt may be adjusted and tensioned without affecting the position of the door panels. For a two speed car door configuration, only one linkage is connected to a door panel since the other door panel is driven by an air cord system (not shown). In a center opening configuration, two identical linkages are used (see Fig. 1). The first linkage connects two ends of the belt to form a continuous shape, as described above. The second linkage, which attaches to the other door panel, is positioned on the upper or lower portion of the belt, depending on the position of the first linkage. The second linkage is assembled in the same manner as the first linkage except that no ends are joined making assembly even easier. This arrangement also falls within the scope of the invention. While the linkage has been described with reference to joining the ends of an elevator door drive belt, it will be appreciated that the invention is not limited to such, and the linkage could be applied to other drive belts for example.

Claims: A linkage (24) for joining a first end (46) and a second end (48) of a first portion of drive belt, said linkage comprising: a second portion (50) of said belt in register with said first end and with said second end, and means for clamping (30,36) said second portion against said first end and said second end such that said drive belt forms a continuous shape. A linkage (24) as claimed in claim 1, further comprising a housing (28) for receiving said first and second ends (46,48). A linkage (24) as claimed in claim 2, wherein said housing (28) is adapted to hold said first end (46) in close proximity to said second end (48), and said means for clamping (30,36) is arranged to clamp said second portion (50) against said first end and said second end of said first portion (14) against said housing. A linkage (24) as claimed in claim 2 or 3, wherein said means for clamping (30,36) is characterized by: a plate (30) having an opening (42), a threaded opening (40) in said housing (28), and a threaded bolt (34) which extends through said opening and mates with said threaded opening. A linkage (24) as claimed in any preceding claim wherein said first portion (14) of said belt has a side having a cross-sectional shape for engaging a drive, and said second portion (50) of said belt also has a side having said cross-sectional shape. A linkage (24) as claimed in any preceding claim wherein said first and second portions (14,50) of belt are provided with interengaging teeth (38) to provide a positive interlock between them. A system for attaching a drive belt (14) to an elevator door (26) comprising a linkage (24) as claimed in any preceding claim adapted to attach said drive belt to said door. A system as claimed in claim 7 when dependent directly or indirectly on claim 2 further comprising a mounting bracket (32) connected to said housing (28) for mounting said belt (14) to said door (26). A system as claimed in claim 8, wherein said bracket (32) is adjustably locatable with respect to said housing (28). A system as claimed in claim 8 or 9 when dependent directly or indirectly on claim 4, wherein said bracket (32) has adjustable means (44,52) for receiving said bolt (34) which extends through said housing (28) to attach said bracket to said housing. An elevator door operator comprising a system as claimed in any of claims 7 to 10 attaching a drive belt to an elevator door.

Inventors: GUCKERT PHILIPPE, MEHLMAN BRUNO P, GUCKERT, PHILIPPE, MEHLMAN, BRUNO P.
Applicants: OTIS ELEVATOR CO, OTIS ELEVATOR COMPANY
Application year: 1992
Main classification: B66B13
IPC codes: B66B13, F16G1, F16G3