WO2007149079A1

WO2007149079A1 - Governor for an elevator system

Info

Publication number: WO2007149079A1
Application number: PCT/US2006/024098
Authority: WO
Inventors: Jose' Miguel Aguado; Andres Monzon; Juan Antonio Quiles; Jose Luis Vergara
Original assignee: Otis Elevator Company
Priority date: 2006-06-21
Filing date: 2006-06-21
Publication date: 2007-12-27

Abstract

An elevator system governor (22) includes a bracket (39) and a pulley (40). The bracket (39) includes a generally planar backplate (50) for facing and mounting to a guide rail (16A). The pulley (40) is mounted to the backplate (50) for receiving a safety rope (28) connected with an elevator car (14).

Description

GOVERNOR FOR AN ELEVATOR SYSTEM

BACKGROUND OF THE INVENTION

The present invention relates to the field of elevator systems. In particular, various embodiments relate to governors for mounting within an elevator hoistway.

In typical elevator systems, a governor assembly is provided for limiting the speed at which the elevator car travels. The governor includes a governor pulley or sheave, often located at one end of the hoistway. A tensioning sheave is positioned near the other end of the hoistway. A rope, which passes over the governor pulley and the tensioning sheave, is fixed to the elevator car with a safety device such that the rope moves as the car moves. When the elevator car moves beyond a threshold speed, the rope causes the governor pulley to rotate at an excessive speed, in turn causing the components of the governor to apply a braking force to the sheave and stop movement of the rope. The stopped rope subsequently trips a safety device on the car, which then triggers a braking system to stop the car.

It is desirable to have elevator systems that occupy the least amount of space, thereby shrinking the size of the hoistway and reducing the otherwise useable space it takes up in a building. Recent elevator systems have included machine room-less designs in which the drive machine, governor and other components have been moved into the elevator hoistway, thus eliminating the need for a machine room above the hoistway. One such machine room-less elevator system is disclosed in European Patent Application 0 849 209 A1 by Miller et al. The Miller et al. application discloses an elevator system in which a governor and cable terminations are mounted atop mounting beams.

Another machine room-less elevator system is disclosed in European Patent Application 1 419 987 A1 by Nishida. The Nishida application discloses an elevator system in which the governor is mounted near the top of one of the guide rails using a support plate, to which the governor is fastened. The support plate is joined to a cable anchor member, which in turn is clipped to the guide rail. The governor is situated such that it straddles both sides of the guide rail and the pulley is positioned between walls of governor such that its axle is supported at both ends.

However, these systems make inefficient use of a plurality of brackets and mounting components that are bulky and still occupy excess hoistway space. It is desirable to decrease the number of components in an elevator system in order to reduce cost and facilitate fast and easy installation of the elevator system. Particularly, for safety reasons, it is desirable to have the governor in place before the elevator car is suspended between the rails with the drive system and belts. Therefore, there is a need for smaller, simpler and more easily installed governor assembly. BRIEF SUMMARY OF THE INVENTION

One embodiment of the present invention is directed to a governor for an elevator system. The governor comprises a bracket and a pulley.

The bracket includes a generally planar backplate for facing and mounting to a guide rail. The pulley is mounted to the backplate for receiving a safety rope connected with an elevator car.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 shows an elevator system in which one embodiment of the present invention is used.

FIG. 2A shows a front view of the car-side of one embodiment of a governor assembly.

FIG. 2B shows a perspective view of the car-side of the governor assembly of FIG. 2A.

FIG. 2C shows a perspective view of the hoistway-wall-side of the governor assembly of FIG. 2A. DETAILED DESCRIPTION

FIG. 1 is a schematic view of underslung elevator system 10 situated in hoistway 12, however, other embodiments of the present invention can be implemented in other elevator systems such as direct roped or overslung systems. Elevator system 10 includes car 14, guide rails 16A and 16B, drive machine 18, counterweight 20, governor 22, safety block 24, tension device 26 and safety rope 28. Car guide rails 16A and 16B are disposed in hoistway 12 between car walls 34A and 34B and hoistway walls 32A and 32B, respectively. Drive machine 18 moves car 14 along rails 16A and 16B via a plurality of ropes. The embodiment in FIG. 1 shows three coated steel belts (CSB) 36 as the ropes. However, any other suitable elevator ropes, such as traditional steel cables, jacketed steel cables, synthetic fiber ropes or the like, in any suitable number, can be used instead of CSBs 36.

Governor 22 is mounted near the top of guide rail 16A. In the machine room-less embodiment shown in FIG. 1, drive machine 18 is located in hoistway 12 at the top of guide rail 16B. Attached near the top of hoistway 12, such as on bracket 37, are terminations that fix first ends of CSBs 36. Opposing second ends of CSBs 36 are connected with terminations 38A - 38C, which in one embodiment of the invention, are located on governor 22. Counterweight 20 and car 14 are suspended on the CSBs 36 between terminations 38A - 38C and bracket 37. Governor 22 is positioned at the top of guide rail 16A and includes bracket 39, which includes portions for mounting with guiderail 16A, receiving other components of governor 22, such as pulley 40 (shown in phantom), and receiving other hardware of elevator system 10, such as terminations 38A - 38C. Governor 22 includes various additional components such as pulley 40, which is positioned on a first laterally extending portion of bracket 39. Governor 22 is used in conjunction with safety block 24, tension device 26 and safety rope 28 to limit the rate of speed at which car 14 travels, and operates in a known manner. In the embodiment show in FIG. 1 , rope 28 is endless, and safety block 24 is connected with the underside of car 14. Bracket 39 allows governor 22 to be mounted on rail 16A expediently by reducing the required amount of space, parts and labor. FIG. 2A shows a car-side view of governor 22. FlG. 2B shows a perspective view of the car-side of governor 22. FIG. 2C shows a perspective view of the hoistway-wall-side of governor 22. FIGS. 2A - 2C are discussed concurrently, and demonstrate the part-reduction and space-saving benefits of governor 22.

Governor 22 includes bracket 39, pulley 40 and axle 42. In other embodiments, governor 22 includes elevator car speed detection elements, such as remote tripping test device 44 and overspeed switch and rearming coil 46. Governor 22 also includes cover 48 (shown in phantom in FIGS. 1 & 2) to protect the components of governor 22.

Pulley 40 and axle 42 are built onto bracket 39 such that governor 22 requires only one member for housing the components of governor 22, and mounting governor 22 with rail 16A. Also, no additional brackets are required for optionally joining terminations 38A - 38C with bracket 39. Bracket 39 comprises seamlessly connected portions for mounting with guide rail 16A, receiving pulley 40 and optionally receiving terminations 38A - 38C. Thus, terminations 38A - 38C and pulley 40 can be mounted with guide rail 16A simultaneously, and bracket 39 can be easily manufactured. Specifically, in the embodiment shown, bracket 39 comprises backplate 50, which is comprised of first portion 52 for mounting on guide rail 16A, second portion 54 for receiving pulley 40, and third portion 56 for receiving terminations 38A - 38C. Backplate 50 is a uni-body plate that can be mounted with the hoistway-wall-side of rail 16A in a generally laterally extending planar orientation, between car wall 34A and hoistway wall 32A.

Bracket 39 also includes flaps 60, 62, 64, and 66, which provide support for pulley 40 and terminations 38A - 38C, and provide structural support to backplate 50. Flaps 60, 62, 64 and 66 are typically shaped by bending various portions of bracket 39. Specifically, second portion 54 includes top flap 60 and side flap 62, which are bent in toward the car- side of governor 22. Third portion 56 includes top flap 64 and side flap 66, which are also bent in toward the car-side of governor 22. Since flaps 60 - 66 are bent in toward the car-side, governor 22 occupies very little space between hoistway wall 32A (FiG. 1) and rail 16A. Pulley 40 and axle 42 are positioned on the car-side of second portion 54 of backplatelate 50, below flap 60. Remote tripping test device 44 and overspeed switch and rearming coil 46 are positioned above flap 60 on the car-side of second portion 54 of backplate 50. Terminations 38A - 38C are positioned below flap 64, which is positioned on the car-side of third portion 56 of backplate 50. Thus, backplate 50 determines the furthest hoistway-wall-side extent of governor 22. This configuration helps reduce the width of governor 22 and reduce the amount of space occupied in hoistway 12. Specifically, governor 22 is more readily positioned between car wall 34A and hoistway wall 32A. The need for mounting a bracket to another bracket or a housing within another housing, which has the effect of doubling wall thickness, is eliminated. Also, governor 22 is mountable below top 68 of rail 16A such that it does not interfere with flange 70 on which car 14 travels. Specifically, by lowering bracket 39 on rail 16A, remote tripping test device 44 and overspeed switch and rearming coil 46 can be mounted on the top of governor 22 such that they project upward from bracket 39 without consuming excessive hoistway space or interfering with rail 16A.

First portion 52 of backplate 50 is mounted with guide rail 16A using threaded fasteners 72. Plates 74 and 76 are joined with backplate 50 on either side of rail 16A to provide structural reinforcement to backplate 50 when terminations 38A - 38C are included with governor 22.

Thus, when terminations 38A - 38C are not included with governor 22, plates 74 and 76 are optional features. Plates 74 and 76 include main portions that are flush with the car-side of backplate 50, and flange portions that extend ninety degrees from the main portions. As shown in the embodiment of FIGS. 2A - 2C, fasteners 78 secure the main portion of plate 74 with backplate 50 on one side of rail 16A, while the main portion of plate 74 is welded with backplate 50 on the other side of rail 16A. Fasteners 78 allow field repairs and installations to be conducted with governor 22. Plates 74 and 76 prevent backplate 50 from rotating or otherwise yielding at its juncture with rail 16A under loading. Plates 74 and 76 also include right-angle flanges that are used to provide three- dimensional bending support to backplate 50. The right-angle flange of plate 76 is also welded to flap 64 to further increase the overall rigidity of bracket 39.

In other embodiments, governor 22 includes additional plates having various shapes or configurations to reinforce backplate 50. In another embodiment, the joint between rail 16A and backplate 50 can be reinforced with the use of additional fasteners instead of plates 74 and 76. In one embodiment, six fasteners are used and are configured to increase resistance to rotational bending of backplate 50 under loading. In other embodiments, backplate 50 is joined with guide rail 16A with other methods, such as welding. In all of these configurations, however, backplate 50 is directly mounted to the hoistway-wall-side of rail 16A, such that no additional brackets or plates are required to link pulley 40 with rail 16A.

Second portion 54 extends seamlessly laterally from first portion 52 of backplate 50 such that it forms a co-planar extent for receiving axle 42 and pulley 40. Pulley 40 is rotatably mounted with the car-side of backplate 50 through axle 42. In one embodiment, axle 42 is mounted flush with backplate 50 with, for example, fasteners 80, such that pulley 40 rotates on axle 42 with the aid of bearings. In such an embodiment, axle 42 includes a base plate or flange on which mounting bores are located for mating with mounting bores of backplate 50. However, in other embodiments, axle 42 can be rotatably mounted with backplate 50 through, for example bearings secured to backplate 50. In this embodiment, pulley 40 is rigidly fixed to and rotates with axle 42. In either configuration, axle 42 is joined with backplate 50 at only one end such that it is cantilevered from backplate 50, thus eliminating the need for supporting a second end of axle 42 thereby reducing the width of governor 22. Pulley 40 is secured with backplate 50 such that it is shielded from the hoistway-wall-side by backplate 50, and at least partially encapsulated within and protected by the confines of backplate 50 formed by flaps 60 and 62. Cover 48 is placed over second portion 54 to further protect pulley 40 and axle 42 and can be joined with backplate 50 using any suitable method, such as with latches, hinges or fasteners 82.

Second portion 54 includes top flap 60 and side flap 62, which are folded inward toward the car-side of rail 16A. Flap 60 provides protection for pulley 40 and provides a platform on which other components, such as remote tripping test device 44, can be mounted. Flap 60 also includes access to pulley 40 such that overspeed switch and rearming coil 46 can be mounted with backplate 50 with threaded fasteners 84, and connected with governor 22. Top flap 60 also adds stability to backplate 50 by increasing the mechanical resistance to bending forces from governor 22 and forces applied to rope 28. Side flap 62 also provides further rigidity and reinforcement to bracket 39 by additionally increasing the bending resistance of backplate 50. For example, flaps 60 and 62 increase the sectional inertia of backplate 50. Flap 62 also provides protection from hoistway 12 for pulley 40 and axle 42. Third portion 56 extends seamlessly laterally from first portion 52 of backplate 50 such that it forms a co-planar extent for joining terminations 38A - 38C with flap 64. Third portion 56 includes top flap 64 and side flap 66 that perform similar protective and stability functions as flaps 60 and 62. Flap 64 also provides load-bearing functions for receiving terminations 38A - 38C. Terminations 38A - 38C are joined with third portion 56 by rod and nut combinations 86A - 86C, respectively. Terminations 38A - 38C receive CSBs 36 at one end and rod and nut combinations 86A - 86C at a second end. The rods are inserted through holes in flap 64 and are prevented from being pulled through the holes by the nuts. Springs or compressible washers can be positioned between flap 64 and the nuts in order to cushion some of the force placed on CSBs 36 by car 14 and counterweight 20. Thus, flaps 60 and 66 provide structural strength and reinforcement to backplate 50 for supporting the weight presented by terminations 38A - 38C, and could be omitted if terminations 38A - 38C were not included with governor 22.

With the various embodiments of the present invention in FIGS. 1 - 2C, governor 22 extends minimally beyond the hoistway-wall-side of guide rail 16A. Similarly, governor 22 and, in other embodiments, terminations 38A - 38C extend minimally beyond the car-side of backplate 50. Thus, governor 22 achieves a low-profile, low-footprint configuration suitable for mounting between car wall 34A and hoistway wall 32A, below top 68.

This configuration achieves several benefits in the design and installation of elevator system 10. First, hoistway 12 does not have to include space beyond top 68 to accommodate governor 22 and bracket 39. Also, being mounted lower on rail 16A allows CSBs 36 and rope 28 to be shortened, which reduces the cost of elevator system 10. The cost of elevator system 10 is further reduced by the elimination of duplicative mounting brackets, housings and hardware. Additional benefits are realized in the installation of bracket 39. With the elimination of additional brackets or housing required for mounting governor 22 with rail 16A, governor 22 is quickly and easily installed in elevator system 10.

Likewise, terminations 38A - 38C can be simultaneously mounted with governor 22 without the use of any further brackets, bracket extensions or mounting steps. This not only has significant time saving advantages, but also safety advantages. Various embodiments of bracket 39 allow governor 22 to be easily installed before car 14 is hung from CSBs 36 with terminations 38A - 38C.

Although the various embodiments of the present invention have been described with reference to examples and preferred embodiments, workers skilled in the art will recognize that changes may be made in form and detail without departing from the spirit and scope of the invention.

Claims

CLAIMS:

1. An elevator system comprising: first and second guide rails extending longitudinally along an elevator hoistway; an elevator car for travelling longitudinally along the first and second guide rails; and a governor comprising: a bracket that includes a generally planar backplate facing and mounted to the first guide rail; and a pulley mounted to the backplate for receiving a safety rope connected with the elevator car.

2. The elevator system of claim 1 wherein the bracket includes a laterally extending portion seamlessly connected with the backplate for receiving terminations for elevator car drive lines.

3. The elevator system of claim 2 and further comprising a reinforcing plate mounted alongside the backplate and the first guide rail to prevent failure of a juncture between the backplate and the first rail.

4. The elevator system of claim 1 wherein the pulley is rotatably connected with the backplate through an axle.

5. The elevator system of claim 4 wherein the axle projects out from the backplate such that it is suspended at only a first end by the backplate.

6. The elevator system of claim 5 wherein the axle is mounted to the backplate with a flange such that the pulley rotates on the axle.

7. The elevator system of claim 5 wherein the axle is joined with a car-side of the backplate.

8. The elevator system of claim 7 wherein the governor is mountable on the first rail such that the backplate forms the furthest hoistway-wall- side extent of the governor.

9. The elevator system of claim 8 wherein the bracket further comprises a top flap positioned over the pulley.

10. The elevator system of claim 9 wherein the top flap provides structural reinforcement to the backplate and protects the pulley.

11. The elevator system of claim 1 wherein the governor is mountable in an elevator hoistway below a top of the first guide rail.

12. An elevator system governor comprising: a bracket that includes a generally planar backplate for facing and mounting to a guide rail; and a pulley mounted to the backplate for receiving a safety rope connected with an elevator car.

13. The governor of claim 12 wherein the bracket includes a portion seamlessly connected with the backplate for receiving terminations for elevator car drive lines.

14. The governor of claim 13 and further comprising a reinforcing plate mounted to the backplate alongside where the bracket is receivable with the guide rail in order to reinforce a juncture between the backplate and the guide rail.

15. The governor of claim 12 wherein the pulley is rotatably connected with the backplate through an axle.

16. The governor of claim 15 wherein the axle projects out from the backplate such that it is suspended at only a first end by the backplate.

17. The governor of claim 16 wherein the axle is mounted to the backplate with a flange such that the pulley rotates on the axle.

18. The governor of claim 16 wherein the axle is joined with a side of the plate for joining with the guide rail.

19. The governor of claim 16 wherein the bracket further comprises a top flap positioned over the pulley for providing structural reinforcement to the backplate and protecting the pulley.

20. The governor of. claim 19 wherein the bracket further comprises a side flap positioned alongside the pulley.