Modular sheave unit

Disclosed is a modular sheave unit including: a bearing that includes an outer race, an inner race and one or more rolling elements therebetween; and a sleeve that includes one or both of: an outer sleeve axially surrounding the outer race, the outer sleeve including an outer surface defining a groove, the groove configured to receive a belt; and an inner sleeve axially surrounded by the inner race and disposed between the inner race and a mandrel.

BACKGROUND

The disclosure relates generally to sheave assemblies for guiding belts that move elevator cars, and more specifically to modular sheave units of a sheave assembly for an elevator car.

Commercial elevator systems may use belt sheaves as part of driving system to operate an elevator car. Drive sheaves are used to both drive and guide belts. Idler sheaves may be located intermediate the drive sheave and the elevator car and may be used to maintain proper alignment and tension of belts during operation. Idler sheaves may have belt receiving grooves with a profile contours that constrict sideway motion of belts to ensure alignment. Manufacturing of idler sheaves with contoured outer surfaces may be costly.

BRIEF DESCRIPTION

Disclosed is a modular sheave unit comprising: a bearing that includes an outer race, an inner race and one or more rolling elements therebetween; and a sleeve that comprises one or both of: an outer sleeve axially surrounding the outer race, the outer sleeve including an outer surface defining a groove, the groove configured to receive a belt; and an inner sleeve axially surrounded by the inner race and disposed between the inner race and a mandrel.

In addition to one or more of the above disclosed features or as an alternate the sleeve comprises the outer sleeve; and the inner race includes the inner surface configured to be positioned against a mandrel.

In addition to one or more of the above disclosed features or as an alternate the sleeve comprises the inner sleeve; and the outer race includes the outer surface that defines the groove.

In addition to one or more of the above disclosed features or as an alternate the sleeve comprises both the outer sleeve and the inner sleeve.

In addition to one or more of the above disclosed features or as an alternate the sleeve is formed from one of aluminum, plastic, thermoplastic polyurethane and rubber.

In addition to one or more of the above disclosed features or as an alternate the sleeve comprises the outer sleeve and the inner sleeve; the outer sleeve is formed from one of aluminum, plastic, thermoplastic polyurethane and rubber; and the inner sleeve is formed from another of aluminum, plastic, thermoplastic polyurethane and rubber.

In addition to one or more of the above disclosed features or as an alternate the bearing is a ball bearing.

Further disclosed is an elevator sheave system comprising: a plurality of the modular sheave units arranged side by side along a mandrel, wherein the plurality of the modular sheave units include one or more of the above disclosed features. The system further includes fastening devices located on opposing ends of the mandrel to secure the modular sheave units to the mandrel.

Further disclosed is a method of configuring a modular sheave unit, comprising arranging, a plurality of modular sheave units, side by side along a mandrel, wherein the plurality of the modular sheave units include one or more of the above disclosed features. The method further includes arranging a fastening device on opposing ends of the mandrel to secure the plurality of modular sheave units to the mandrel.

DETAILED DESCRIPTION

FIG. 1is a perspective view of an elevator system101including an elevator car103, a counterweight105, a tension member107, a guide rail109, a machine111, a position reference system113, and a controller115. The elevator car103and counterweight105are connected to each other by the tension member107. The tension member107may include or be configured as, for example, ropes, steel cables, and/or coated-steel belts. The counterweight105is configured to balance a load of the elevator car103and is configured to facilitate movement of the elevator car103concurrently and in an opposite direction with respect to the counterweight105within an elevator shaft117and along the guide rail109. The tension member107engages the machine111, which is part of an overhead structure of the elevator system101. The machine111is configured to control movement between the elevator car103and the counterweight105. The controller115is located, as shown, in a controller room121of the elevator shaft117and is configured to control the operation of the elevator system101, and particularly the elevator car103, for example, to stop at one or more landings125.

InFIGS. 2 and 3, an elevator sheave system200and modular sheave units220thereof are illustrated, which may employ various features of the disclosed embodiments, and wherein one modular sheave unit220is illustrated inFIG. 3. The modular sheave units220may each include an outer annulus201, an inner annulus202, a fixing frame203, two annular rows of ball bodies204and seal rings205. The outer annulus201is provided with a belt receiving groove211on its radial outer surface to support, and guide, a belt. The belt receiving groove211may have a belt seating portion311which may be an axial center portion having an arcuate convex curvature forming a belt seat and opposing flanged side walls312for centering and providing transition fit with a belt. This configuration reduces the friction against a belt disposed against the belt receiving groove211and increase a usage life of the modular sheave unit220.

The two rows of ball bodies204may be respectively seated on axial left (distal) and right (proximate) sides of radial inner ball seating grooves212of the outer annulus201and axial left and right sides of radial outer ball seating grooves221of the inner annulus202. The fixing frame203may secure the rows of ball bodies204between the outer annulus201and the inner annulus202. As can be appreciated, the outer annulus201and inner annulus202are configured to be respective outer and inner races of a ball bearing structure formed by the sheave system200. The axial end faces of the outer annulus201and the inner annulus202may be provided with radially opposing seal ring grooves206. The seal ring205may be provided in the seal ring grooves206between the outer annulus201and the inner annulus202.

The sheave system200includes a mandrel210and a plurality of the modular sheave units220arranged axially side by side along the mandrel210. The modular sheave unit220and the outer surface of the mandrel210may form a transition fit. Axial end faces of the inner annulus202of axially adjacent modular sheave units220may be axially pressed against each other. Axial end faces of the outer portion201of axially adjacent modular sheave units220may be axially spaced from each other to allow relative rotation therebetween. Abrasion resistance paddings207may be arranged between the axial end faces of the inner annulus202of axially adjacent modular sheave units220. This configuration reduces friction between the adjacent modular sheave units220and further increases usage life of the modular sheave units220. Jump rings may be used on the axial ends of the mandrel210to secure the modular sheave units220to the mandrel210.

Various issues may result with the above disclosed modular sheave units. Manufacturing modular sheave units as disclosed above may result in significant costs. Moving surfaces may need to be plated. If damaged, such units may be difficult to repair and replace.

Turning now toFIGS. 4a-4c, modular sheave units500are disclosed according to one or more embodiments, wherein each ofFIG. 4a-4cillustrates a single module sheave unit500. The modular sheave units500may each include a bearing510that spans a width W1, which is an axial length relative to an axis of rotation for the bearing510. The width W1may be the same as that of a belt receiving groove520of the modular sheave units500, wherein the belt receiving groove520has the same features of the belt receiving groove211identified above.

The bearing510may be a ball bearing with an inner race530, an outer race540, rolling elements545, fixing elements546, and seal rings547, manufactured from materials that are strong enough for the bearing operation. The ball bearing510may be, for example, an off-the-shelf product and/or a product having a generalized design that is usable across various elevator sheave configurations and platforms. The use of a generic and interchangeable ball bearing510may reduce customization requirements as compared with modular sheave units220usable for only specific configurations or platforms.

A radial outer sleeve (outer sleeve)550(FIG. 4a), which may be an outer annulus, may be placed over the bearing outer race540. The outer sleeve550may have the same width W1as the bearing510and may comprise one or more corrosion resistant, energy absorption materials comprising aluminum, plastic, thermoplastic polyurethane (TPU) and rubber. By including an outer sleeve550with a generic ball bearing510, the modular sheave units500may be customized without the need for additional surface treatments, such as plating, to the bearing510.

A radial inner sleeve (inner sleeve)560, which may be an inner annulus, may utilized alternatively (FIG. 4b) or in addition (FIG. 4c) to the outer sleeve550, and may be placed inside the bearing inner race530. In embodiments with an inner sleeve560and without the outer sleeve550(FIG. 4b), the outer race540of the bearing510may be formed with the belt receiving groove520. The inner sleeve560may comprise the same or different energy absorption material as the outer sleeve550. Both the outer sleeve550and the inner sleeve560may be molded or casted to minimize machining. Thus, the modular sheave500units may be individually and inexpensively replaced when damaged, so that it is easier to maintain and reduce repairing costs.

Illustrated inFIG. 4cis an embodiment in which the inner sleeve560has a width W2that is larger than the width W1of the bearing510and the outer sleeve550. This provides for axial spacing between adjacent modular sheave units500, as further illustrated inFIGS. 5a-5b. Turning now toFIGS. 5a-5b, a plurality of the modular sheave units500are illustrate in a sheave system600. The sheave system600includes a mandrel610that may be similar in configuration to the mandrel210disclosed above. The modular sheave units500may be configured against the mandrel610similarly to the configuration between the modular sheave units220and the mandrel210disclosed above. In addition, set screws620or other fastening devices may be on axial ends630of the mandrel610to secure the modular sheave units500against the mandrel610. As indicated withFIG. 4c, the modular sheave units500may have respective inner sleeves560with widths W2that are larger than the widths W1for the respective outer sleeves550and bearings510. Thus, when the inner sleeves560of adjacent pairs of the modular shave units500are pressed against each other there is a separation between the bearings510and the outer sleeves550. This configuration enables relative rotation between adjacent ones of the modular sheave units500. Abrasion resistance paddings, however, may not need to be used between adjacent modular sheave units500because the inner sleeves550may provide the same function of reducing the occurrence of abrasion between the adjacent modular sheave units500.