HK1190688B - Elevator system including a 4:1 roping arrangement - Google Patents

Description

The method comprises the following steps: 1 Elevator System with roping arrangement

Background

Elevator systems have proven useful for transporting passengers between different floors of a building. A variety of different elevator system configurations can be achieved. A traction-based elevator system includes a roping arrangement that supports the weight of an elevator car and a counterweight. The machine drives a traction sheave that moves a roping member to cause desired movement of the elevator car.

Various roping arrangements are known in the industry. The most straightforward roping arrangement is considered to be 1: 1 roping arrangement wherein the movement of the roping means is the same as the corresponding amount of movement of the elevator car. In the following step 2: 1 roping arrangement the roping means movement is twice as much as the corresponding movement of the elevator car. 4: 1 roping arrangements have been proposed and include approximately four times as many roping member movements as the corresponding movements of the elevator car.

The ability to achieve different roping arrangements is more complex with the introduction of a flat belt suspension member instead of a round steel wire rope. U.S. patent application publication No. us2008/0121468 discloses a possible 4: 1 hanging the rope. This document proposes an arrangement comprising a stacked arrangement of diverting pulleys on one side of the hoistway. One disadvantage associated with this arrangement is that it requires more vertical space within the hoistway to accommodate the arrangement of the sheaves. Minimizing the amount of hoistway space required for an elevator system is a continuing challenge within the elevator industry.

Disclosure of Invention

An exemplary elevator system includes an elevator car. At least one guide rail guides movement of the elevator car. The guide rail has a length in the direction of movement of the elevator car and a depth substantially perpendicular to the length. The plurality of flat belts are positioned relative to the elevator car such that movement of the flat belts for causing movement of the elevator car is approximately four times a corresponding movement of the elevator car. The first plurality of sheaves is positioned to guide the flat belt as the belt is wrapped at least partially around the first plurality of sheaves. A first plurality of pulleys remain fixed near one end of the guide rail. The first plurality of pulleys rotate about coaxially aligned axes and have an overall width along the axes that is no greater than a depth of the guide rail.

In another exemplary elevator system, the elevator system can additionally include a plurality of second sheaves. The plurality of first pulleys and the plurality of second pulleys may each be located on opposite sides of the guide rail.

In another exemplary elevator system, the first plurality of sheaves can total two sheaves and the second plurality of sheaves can total two sheaves.

In another example elevator system that includes the components of any of the foregoing elevator systems, the plurality of flat belts may total two belts.

In another example elevator system including the components of any of the foregoing elevator systems, the overall width can be less than the depth of the guide rail.

In another example elevator system that includes the components of any of the foregoing elevator systems, the total width can be equal to the depth of the guide rail.

In another example elevator system including the members of any of the foregoing elevator systems, the overall width can be between 60mm and 75 mm.

In another example elevator system including the members of any of the foregoing elevator systems, the flat belts may each have a width parallel to a width of the plurality of first sheaves, the belt width being between approximately 10mm to 15 mm.

In another example elevator system including the components of any of the foregoing elevator systems, the guide rail can be fixed to the hoistway wall, and the coaxial axis and the depth of the guide rail can be substantially perpendicular to the hoistway wall.

In another exemplary elevator system including the components of any of the foregoing elevator systems, the elevator system can additionally or alternatively include a plurality of car sheaves supported on the elevator car for guiding the flat belts over the elevator car. The plurality of car sheaves is rotatable about a car sheave axis that is perpendicular to the coaxially aligned axes of the plurality of first sheaves.

In another example elevator system that includes the components of any of the foregoing elevator systems, the plurality of car sheaves can be positioned below the plurality of first sheaves such that a section of each of the flat belts between the plurality of first sheaves and the plurality of car sheaves is oriented vertically straight and parallel to the direction of elevator car movement.

In another example elevator system that includes the components of any of the foregoing elevator systems, the elevator system can additionally or alternatively include a counterweight associated with the elevator car, the flat belt suspending the elevator car and the counterweight.

In another example elevator system including the components of any of the foregoing elevator systems, the elevator system can additionally or alternatively include a plurality of counterweight sheaves supported for movement with the counterweight, at least a first one of the counterweight sheaves being closer to a side of the counterweight than a second one of the counterweight sheaves to thereby suspend the counterweight in a substantially centered manner about a center of gravity of the counterweight.

In another example elevator system including the components of any of the foregoing elevator systems, the first and second counterweight sheaves can be aligned with each other and with a single vertical plane oriented at an oblique angle relative to a side of the counterweight.

In another example elevator system including the components of any of the foregoing elevator systems, the elevator system can include five counterweight sheaves supported on a counterweight for movement with the counterweight within a hoistway. Furthermore, all five counterweight sheaves may be aligned in a single vertical plane.

In another example elevator system that includes the components of any of the foregoing elevator systems, the plurality of belts can follow a path from one end of the belt, below the elevator car, and to the traction sheave. Further, a first one of the belts may follow a first path from the traction sheave, around the plurality of diverting pulleys supported on the counterweight, and to the other end of the first one of the belts, while a second one of the belts may follow a second, different path from the traction sheave, around the plurality of pulleys supported on the counterweight, and to the other end of the second one of the belts.

In another example elevator system that includes the components of any of the foregoing elevator systems, the plurality of sheaves supported on the counterweight can all be aligned with each other and with a single vertical plane.

Various features and advantages of the disclosed exemplary embodiments will become apparent to those skilled in the art from the following detailed description. The drawings that accompany the detailed description can be briefly described as follows.

Drawings

Figure 1 schematically illustrates selected portions of an elevator system including a roping arrangement designed according to an embodiment of this invention.

Figure 2 diagrammatically shows selected features of the example of figure 1.

FIG. 3 schematically illustrates another selected feature of the example embodiment.

FIG. 4 is a cross-sectional view of an exemplary flat band.

FIG. 5 schematically illustrates another selected feature of the example embodiments.

Detailed Description

Fig. 1 illustrates selected portions of an elevator system 20, the elevator system 20 including a car 32 and a counterweight 62, both of which are configured to move vertically (in opposite directions) in a hoistway 92 (a portion of which is shown removed in fig. 1 for ease of viewing). The car 32 moves along the car guide rails 40, 41. Similarly, the counterweight 62 moves along the counterweight guide rails 61, 63. Straps 22 and 24 are located at 4: 1 in a roping arrangement. The arrangement of the flat belts 22 and 24 and the manner in which they are guided by the sheaves about the path of travel results in movement of the belts 22 and 24 for movement of the elevator car 32, the movement of the belts 22 and 24 being approximately four times the corresponding movement of the elevator car 32.

One end of each of the belts 22 and 24 is secured near the top of the hoistway by a respective terminal 26. A first portion 28 of the belt extends vertically downward from the terminal end 26 to a sheave 30 that guides the belt below an elevator car 32. A second portion 33 of the belt extends below the elevator car 32 between the sheaves 30 and 34. A third portion 36 of the belts 22 and 24 extends vertically upward along one side of the elevator car 32.

Pulleys 38 and 44 are located at a fixed vertical position near the top of guide rail 40. A third portion 36 from pulley 34 extends to pulley 38. A fourth portion 42 of the belts 22 and 24 extends between the pulley 38 and a pulley 44. A fifth portion 46 of the belt extends vertically downward to a sheave 47 supported on the elevator car 32. A sixth portion 48 of the belt extends between the sheave 47 and a sheave 50 also supported on the elevator car 32.

A seventh portion 52 of the belts 22 and 24 extends vertically upward from the pulley 50 to a traction pulley 54 driven by a machine 56. After being partially wrapped around the traction sheave 54, the belts 22 and 24 include eighth vertically falling portions 58 and 80 that extend downward toward the counterweight 62. In this regard, it can be noted that the first and seventh portions 28 and 52 of the belts 22 and 24 follow similar paths (i.e., parallel and side-by-side with each other) between the car 32 and either (i) the respective terminal 26 (first portion 28) or (ii) the traction sheave 54 (seventh portion 52). On the other side of the traction sheave 54, however, the belts 22 and 24 do not follow the same path. The illustrated example includes a unique arrangement of belts and pulleys on the counterweight side of the hoistway 92 to allow the counterweight to move very close to the top of the hoistway 92 without introducing significant drag angles (drawangles) in the belts. This arrangement minimizes or eliminates any misalignment of the belt and pulleys on the counterweight side of the hoistway 92.

The eighth section 58 of the belt 24 in this example extends from the traction sheave 54 down to a sheave 60 supported on a counterweight 62. A lateral portion 64 of the belt 24 extends between the pulley 60 and a pulley 66 also supported on the counterweight 62. A vertically upwardly extending ninth portion 68 of the belt 24 is located between the pulley 66 and a pulley 70 supported above the counterweight 62 near the top of the hoistway 92. The tenth section 72 of the belt 24 extends down to a pulley 74 supported on the counterweight 62. A final eleventh portion 76 of the belt 24 extends vertically between the pulley 74 and a terminal end 78 held in a fixed position, which in this example is near the top of the hoistway 92.

The belt 22 follows a different path in which an eighth portion 80 thereof extends downwardly from the traction sheave 54 to a sheave 82 supported on the counterweight 62. Thereafter, instead of having a lateral portion corresponding to the lateral portion 64 of the belt 24, the belt 22 is wrapped partially around the pulley 82 such that the ninth portion 84 extends vertically upward to a pulley 86 supported near the top of the hoistway 92. The tenth section 88 of the belt 22 extends downwardly from the pulley 86 to a pulley 90 supported on the counterweight 62. The belt 22 includes a final eleventh portion 93 that extends between the pulley 90 and a terminal end 94 supported at a fixed location near the top of the hoistway 92.

The manner in which the sheaves are supported below the elevator car 32, on the counterweight 62, or near the top of the hoistway 92 is not shown for simplicity of illustration. Those skilled in the art who have the benefit of this description will recognize how to support the sheaves in corresponding positions to meet their particular needs. Similarly, the manner in which the terminal and machine are supported near the top of the hoistway 92 is not shown.

One feature of an exemplary arrangement is shown in fig. 2. The pulleys 38 and 44 located near the top of the guide rail 40 are arranged parallel to each other and perpendicular to the pulleys 34 and 47 that are parallel to each other. The pulley 38 in this example includes two pulleys having coaxially aligned axes of rotation shown schematically at 180. Pulley 44 also includes two pulleys rotating about coaxially aligned axes shown schematically at 182. Pulleys 34 and 47 each comprise two pulleys and they all rotate coaxially about a single axis shown schematically at 184. The arrangement of pulleys 38, 44, 34 and 47 allows for an almost straight vertical drop of sections 36 and 46 of belts 22 and 24. The almost straight vertical drop in this example includes portions 36 and 46 that are parallel to the length of the guide rails 40 (i.e., the direction of movement of the elevator car 32). The perpendicular orientation of axis 184 relative to axes 180 and 182 results in twisting of straps 22 and 24 along each of portions 36 and 46. This arrangement minimizes the amount of pull on the belt and facilitates better tracking (track) of the belt over the pulley.

Another feature of the illustrated example is shown in fig. 3, which is an elevation view from above of the guide rail 40 in this example. The guide rail 40 is secured to the hoistway wall 190 using, for example, known brackets. A portion of the guide rail 40 includes a guide surface 192 along which the elevator guide member travels as the elevator car 32 moves vertically in response to movement of the belts 22 and 24 by the machine 56 and the traction sheave 54. The guide rail 40 has a longitudinal length dimension extending vertically in the hoistway (i.e., into the page of fig. 3) and a depth dimension D perpendicular to the length of the guide rail 40. In the example shown, the depth dimension is measured in a direction generally perpendicular to the surface of the well wall 190.

Pulleys 38 and 44 each have an overall width shown at w in fig. 3 along their respective coaxially aligned axes of rotation. The overall width w is no greater than the depth D of the rail 40. This arrangement allows the sheaves 38 and 40 to be conveniently fitted in the limited space between the elevator car 32 and the hoistway wall 190. In one example, the depth D is in a range between 60mm and 75 mm. The total width w is in the same range. In one example, the total width w is equal to the depth D.

In the example shown, the pulley 38 is shown as two separate wheels coaxially aligned along the axis of rotation 180. In another example, the pulley 38 is formed as two distinct belt guide grooves on a single cylinder or wheel. For purposes of this description, either type of configuration is considered a plurality of pulleys that are coaxially aligned (i.e., either configuration guides more than one belt 22, 24 along the desired roping path, and each belt may be considered to engage its own pulley). The same is true with respect to pulley 44 in the example of fig. 3, and pulleys 30, 34, 47, 50, 54, 60, 66, 70, and 74 shown in fig. 1.

The example of fig. 3 includes a mounting structure 194 that supports the axes 180, 182 of the pulleys 38 and 44 in a fixed position relative to the guide rail 40. In this example, the mounting structure 194 is at least partially supported by the rail 40.

One way in which the overall width w is maintained within the depth dimension D is through the use of narrow strips 22 and 24. Fig. 4 is a cross-sectional view of an exemplary belt 22. The polymer jacket 100 surrounds a plurality of tensile members 102, which in one example comprise steel cords. The exemplary belt 22 of fig. 4 includes five tensile members 102. Another example includes four tensile members 102. The foregoing discussion of possible configurations of belt 22 applies equally to belt 24.

The use of fewer tension members in the flat belts and narrower belts as compared to an elevator system including up to 12 such tension members facilitates fitting all of the belts needed to support the load of the elevator car 32 and counterweight 62 and guiding them around the sheaves within the space occupied by the depth D of the guide rail 40. 4: the 1-cord arrangement reduces the load supported by each belt and smaller belts can be used.

Fig. 5 illustrates another feature of an exemplary embodiment. The pulleys 60, 66, 74, 82, and 90 are positioned relative to the counterweight 62 to achieve a balanced suspension of the counterweight 62 about its center of gravity. In this example, the pulley 60 is positioned closer to one side 104 of the counterweight 62, while the pulley 74 is positioned closer to the opposite side 106. The path that the lateral portion 64 of the belt 24 follows between the pulleys 60 and 66 is only partially visible in fig. 5 because the pulleys 82 and 90 are also shown. As can be appreciated from the illustration, each of the pulleys is aligned in a single vertical plane, schematically shown at 108, at an oblique angle relative to the sides 104 and 106 of the counterweight 62. Distributing the positions of the pulleys around the counterweight in this manner allows the counterweight 62 to be suspended about the center of gravity of the counterweight 62 in a direction between the sides 104 and 106 and in a vertical direction (e.g., from right to left according to the figure). This arrangement provides operational efficiency with respect to guiding the counterweight 62 along the vertical travel path.

Additionally, as mentioned above, the placement of the pulleys on the counterweight side of the hoistway 92 (including the pulleys supported on the counterweight 62) allows for maintaining the vertical alignment of the portion of the belt on that side of the hoistway in a manner that minimizes any pull angles. This minimizes or eliminates any misalignment and allows the counterweight 62 to move very close to the top of the hoistway 92. The farther up the counterweight 62 moves, the greater the pull angle will be caused in the presence of any misalignment. The balanced and coplanar alignment of the sheaves on the counterweight side avoids large pull angles.

The illustrated example and the features discussed above provide 4: 1 roping arrangement that minimizes space requirements, provides improved belt tracking along a desired roping path, and facilitates efficiency in elevator system operation. For example, with 4: the ability to use a 1-roping arrangement allows for the use of smaller machines 56, which provides savings in equipment cost and power consumption. The smaller belts 22 and 24 can be guided around the roping path using relatively small and inexpensive pulleys, which provides additional cost savings. A smaller machine 56 and smaller belts 22 and 24 may be used because 4: the 1-roping arrangement reduces the load supported by the belt and the amount of torque required to move the elevator car 32.

The preceding description is exemplary rather than limiting in nature. Variations and modifications to the disclosed examples may become apparent to those skilled in the art that do not necessarily depart from the essence of this invention. The scope of legal protection given to this invention can only be determined by studying the following claims.

Claims (17)

1. An elevator system, comprising:

an elevator car;

at least one guide rail that guides movement of the elevator car, the guide rail having a length in a direction of movement of the elevator car and a depth that is generally perpendicular to the length;

a plurality of flat belts positioned relative to the elevator car such that movement of the flat belts for causing movement of the elevator car is approximately four times a corresponding movement of the elevator car; and

a plurality of first pulleys around which the flat belt is at least partially wrapped, the plurality of first pulleys remaining fixed near one end of the guide rail, the plurality of first pulleys rotating about coaxially aligned axes and having an overall width along the axes that is no greater than a depth of the guide rail.

2. The elevator system of claim 1, comprising a plurality of second sheaves, and wherein the plurality of first sheaves and the plurality of second sheaves are each located on opposite sides of the guide rail.

3. The elevator system of claim 2, wherein the first plurality of sheaves totals two sheaves and the second plurality of sheaves totals two sheaves.

4. The elevator system of claim 1, wherein the plurality of flat belts total two.

5. The elevator system of claim 1, wherein the overall width is less than a depth of the guide rail.

6. The elevator system of claim 1, wherein the total width is equal to a depth of the guide rail.

7. The elevator system of claim 1, wherein the overall width is between 60mm and 75 mm.

8. The elevator system of claim 1, wherein the flat belts each have a width parallel to a width of the plurality of first sheaves, the width of the flat belts being between 10mm and 15 mm.

9. The elevator system of claim 1, wherein the guide rail is fixed to a hoistway wall, and the coaxial axis and the depth of the guide rail are substantially perpendicular to the hoistway wall.

10. The elevator system of claim 1, comprising:

a plurality of car sheaves supported on the elevator car for guiding the flat belt over the elevator car, and wherein the plurality of car sheaves rotate about a car sheave axis that is perpendicular to the coaxially aligned axes of the plurality of first sheaves.

11. The elevator system of claim 10, wherein the plurality of car sheaves are positioned below the plurality of first sheaves such that a section of each of the flat belts between the plurality of first sheaves and the plurality of car sheaves is oriented vertically straight and parallel to a direction of elevator car movement.

12. The elevator system of claim 1, comprising a counterweight associated with the elevator car, the flat belt suspending the elevator car and the counterweight.

13. The elevator system of claim 12, comprising a plurality of counterweight pulleys supported for movement with the counterweight, at least a first one of the counterweight pulleys being closer to a side of the counterweight than a second one of the counterweight pulleys to thereby suspend the counterweight in a substantially centered manner about a center of gravity of the counterweight.

14. The elevator system of claim 13, wherein the first counterweight sheave and the second counterweight sheave are aligned with each other and with a single vertical plane oriented at an oblique angle relative to a side of the counterweight.

15. The elevator system of claim 14, comprising five counterweight sheaves supported on the counterweight for movement with the counterweight within a hoistway, and wherein all five counterweight sheaves are aligned within the single vertical plane.

16. Elevator system according to claim 1,

the plurality of flat belts follow a path from one end of the flat belts, below the elevator car, and to a traction sheave;

a first one of the flat belts following a first path from the traction sheave, around a plurality of sheaves supported on a counterweight, and to another end of the first one of the flat belts; and is

A second one of the flat belts follows a second different path from the traction sheave, around a plurality of sheaves supported on the counterweight, and to the other end of the second one of the flat belts.

17. The elevator system of claim 16, wherein the plurality of sheaves supported on the counterweight are all aligned with each other and with a single vertical plane oriented at an oblique angle relative to a side of the counterweight.