GB2174173A - Sheaves for cable-drawn transportation system - Google Patents

Sheaves for cable-drawn transportation system Download PDF

Info

Publication number
GB2174173A
GB2174173A GB08609183A GB8609183A GB2174173A GB 2174173 A GB2174173 A GB 2174173A GB 08609183 A GB08609183 A GB 08609183A GB 8609183 A GB8609183 A GB 8609183A GB 2174173 A GB2174173 A GB 2174173A
Authority
GB
United Kingdom
Prior art keywords
sheave
cable
groove
sheaves
uhmwpe
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
GB08609183A
Other versions
GB8609183D0 (en
Inventor
William H Gibson
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Otis Elevator Co
Original Assignee
Otis Elevator Co
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Otis Elevator Co filed Critical Otis Elevator Co
Publication of GB8609183D0 publication Critical patent/GB8609183D0/en
Publication of GB2174173A publication Critical patent/GB2174173A/en
Withdrawn legal-status Critical Current

Links

Classifications

    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16HGEARING
    • F16H55/00Elements with teeth or friction surfaces for conveying motion; Worms, pulleys or sheaves for gearing mechanisms
    • F16H55/32Friction members
    • F16H55/36Pulleys
    • F16H55/48Pulleys manufactured exclusively or in part of non-metallic material, e.g. plastics

Landscapes

  • Engineering & Computer Science (AREA)
  • General Engineering & Computer Science (AREA)
  • Manufacturing & Machinery (AREA)
  • Mechanical Engineering (AREA)
  • Pulleys (AREA)
  • Ropes Or Cables (AREA)

Abstract

A sheave 18 for cooperating with a cable 12 is made from ultra- high-molecular-weight polyethylene (UHMWPE). The groove angle A is selected according to the coefficient of friction of the UHMWPE so as to prevent the cable from climbing out of the sheave groove. The low coefficient of friction of UHMWPE makes possible a very shallow groove. <IMAGE>

Description

SPECIFICATION Sheaves for Rope-Drawn Transportation System Technical Field of the Invention The invention relates to pulleys, or sheaves that cooperate with cables, such as in funicu lar-type transportation systems.
Background of the Invention Transportation systems are known in which a vehicle is drawn by a cable.For runs of appreciable length, the cable must be supported every thirty meters or so by grooved sheaves.
Due to the twist of the cable, and the tension thereon, there is a tendency for the cable to climb out of the sheave groove.
Steel sheaves are the norm. They are inexpensive and durable, and their smooth hard surface reduces the tendency for the cable to climb out of the groove. However, they impart a significant amount of wear to the cable.
Rubber, or rubber-lined steel sheaves are expensive and less durable than their steel counterparts, but they are much easier on the cable.
Disclosure of the Invention Therefore, it is an object of this invention to provide a sheave that is both inexpensive and durable, and that tends to keep the cable in the groove without wearing on the cable.
According to the first invention, sheaves are fabricated from ultra-high-molecular-weight polyethylene (UHMWPE) and the groove angle is reduced according to the coefficient of friction of the UHMWPE.
Other objects, features and advantages of the invention will become more apparent in light of the following description of an example thereof.
Brief Description of the Drawings Figure 1 is a perspective view showing sheaves according to this invention in use in a cable-drawn transportation system; and Figure 2 is an edge-on view of a sheave, typical of the sheaves in Fig. 1.
Detailed Description Figure 1 shows a transportation system wherein a car 10 is attached to a cable 12 and moved thereby along a smooth track 14.
The car rides on a cushion of air as provided by hoverpads 16. Sheaves 18, disposed every thirty meters, or so, along the track accommodate cable sag. The transportation system of Fig. 1 is representative of the OTIS SHUT TLE.
Figure 2 shows a sheave 18 which is essentially a disc having two sides 20, 22 and a circumferential edge 24. The edge 24 is not flat, but is formed as a groove to cooperate with the cable 12. Since the sheave must turn in response to cable motion, it is attached via a suitable axle 26 journaled to suitable support means 28 on the track.
The outer edge 24 of the sheave is generally V-shaped, concave towards the center of the sheave, and forms an angle A with respect to an imaginary surface 28, which represents the side of the squat cylindrical disc from which the sheave may be machined.
The groove 24 is symmetrical from side-toside, forming two ears 30 and 32. At the apex of the groove it abruptly becomes approximately quarter-circular in a region 34, with a radius corresponding to the radius of the cable 12.
In the Otis Shuttle, cable tensions of 45,000 Newtons and velocities of 10 meters per second are common. Furthermore, the track does not always follow a straight and level course.
Although the sheaves may be inclined to provide both lateral and vertical suport tq the cable in inclines and curves, the cable will still try to climb out of the sheave.
The coefficient of friction of the sheave and the angle of the groove are key factors in maintaining the cable in the groove. The higher the coefficient of friction, the easier it is for the cable to climb out of the groove.
The shallower the groove, the easier it is for the cable to climb out of the groove. Therefore, on the one hand, it is necessary to make the sheave groove as deep as possible. However, on the other hand, the deeper the groove, the flimsier the ears 30, 32 will become for a sheave of a given size. There is no analogous limit to reducing the coefficient of friction. Simply stated, the slipperier the groove, the better.
The invention resides in the use of an ultrahigh-molecular-weight polyethylene (UHMWPE), such as HOSTALENtGUR, for the sheave material, in the selection of a groove angle, and in the unexpected advantages of this unique combination of features as applied to a cabledrawn vehicle. HOSTALEN"GUR is available from American Hoechst Corporation, Plastics Division, 289 North Main Street, Leominster, Massachusetts 01453, and is described in detail in Designing with the toughest of all plastics, Plastics Design Forum, May/June 1978.
As applied to the sheave of this invention, UHMWPE exhibits outstanding features. It is defined as a linear homopolymer of polyethylene which may have an intrinsic viscosity of 16 or greater. It is extraordinarily tough, yet its paraffin-like surface resists cable abrasion and is easy on the cable. It is easily machined, and has a low coefficent of friction.
Concerning the latter, the inventor has selected a sheave groove angle that is related to the coefficient of friction to prevent the cable from climbing out of the groove.
The coefficient of friction for HOSTALEN "GUR is approximately 0.1. Therefore the slope, or tangent, of the groove must also be at least 0.1 to give a critical sheave groove angle "A" of approximately 6 degrees. We have found that a groove angle of about 25 degrees provides a sheave of adequate strength and provides a safety factor of about 4.
As stated herein before, the disadvantage of increasing the groove angle is weakening the groove ears. With UHMWPE, a much lower groove angle can be employed which results in a stronger, smaller sheave.
It should be understood that the invention has been described with respect to a particular embodiment thereof, and that various additions and changes can be made thereto without departing from the scope of the invention.

Claims (6)

1. A sheave for supporting a movable cable under tension, characterized in that said sheave is made from ultra-high-molecularweight polyethylene (UHMWPE).
2. A sheave according to claim 1 wherein the sheave has an angled groove disposed about its circumference for receiving the moving cable, and the angle of the groove is selected according to the coefficient of friction of the UHMPE.
3. A sheave according to claim 1 or 2 wherein the coefficient of friction for the UHMWPE is of the order of the order 0.1 and the groove angle of the sheave is at least 6 degrees.
4. A sheave according to claim 1, 2, or 3 wherein the groove angle of the sheave is substantially 25 degrees.
5. A sheave for supporting a moving cable under tension, substantially as hereinbefore described with reference to the accompanying drawing.
6. A transportation system comprising a cable-drawn vehicle wherein the cable is supported by a plurality of sheaves as claimed in any preceding claim.
GB08609183A 1985-04-15 1986-04-15 Sheaves for cable-drawn transportation system Withdrawn GB2174173A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US72358385A 1985-04-15 1985-04-15

Publications (2)

Publication Number Publication Date
GB8609183D0 GB8609183D0 (en) 1986-05-21
GB2174173A true GB2174173A (en) 1986-10-29

Family

ID=24906862

Family Applications (1)

Application Number Title Priority Date Filing Date
GB08609183A Withdrawn GB2174173A (en) 1985-04-15 1986-04-15 Sheaves for cable-drawn transportation system

Country Status (6)

Country Link
AU (1) AU582839B2 (en)
CA (1) CA1243295A (en)
DE (1) DE3611258A1 (en)
FR (1) FR2582372A1 (en)
GB (1) GB2174173A (en)
ZA (1) ZA862007B (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105173970A (en) * 2015-09-29 2015-12-23 上海化工研究院 Elevator sliding guide shoe liner made of ultra-high molecular weight polyethylene and preparation method for elevator sliding guide shoe liner

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP4683863B2 (en) * 2003-06-19 2011-05-18 インベンテイオ・アクテイエンゲゼルシヤフト Elevator for load transportation by movable traction means
WO2013165438A1 (en) 2012-05-04 2013-11-07 Otis Elevator Company Methods and apparatuses for applying a substrate onto an elevator sheave

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4034616A (en) * 1975-10-16 1977-07-12 Rauscher David A Pulley means

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE513947C (en) * 1929-04-08 1930-12-06 Adolf Bleichert & Co A G Drive roller for cable cars
DE1906054U (en) * 1964-05-19 1964-12-10 Tefabag Maschinen Und Seilbahn CABLEWAY IMPACTOR.
DE1900707B2 (en) * 1969-01-08 1973-07-05 PROCESS AND BULK FOR MANUFACTURING ROPE ROLLS
FR2525981B1 (en) * 1982-04-28 1985-06-07 Creissels Denis CABLE WITH TWO TRACTOR CARRIER CABLES

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4034616A (en) * 1975-10-16 1977-07-12 Rauscher David A Pulley means

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105173970A (en) * 2015-09-29 2015-12-23 上海化工研究院 Elevator sliding guide shoe liner made of ultra-high molecular weight polyethylene and preparation method for elevator sliding guide shoe liner

Also Published As

Publication number Publication date
CA1243295A (en) 1988-10-18
AU582839B2 (en) 1989-04-13
DE3611258A1 (en) 1986-10-23
GB8609183D0 (en) 1986-05-21
FR2582372A1 (en) 1986-11-28
AU5528386A (en) 1986-10-23
ZA862007B (en) 1987-03-25

Similar Documents

Publication Publication Date Title
JP2807037B2 (en) Sliding shoe for slide roof, slide tilt roof, etc.
KR100716101B1 (en) Improved sheave design
GB2206220B (en) Optical fibre cables
US3623590A (en) Moving handrail system
AU693542B2 (en) Elevator machinery and its installation
WO1991017900A3 (en) Low friction, abrasion resistant polymer coating
GB2174173A (en) Sheaves for cable-drawn transportation system
FI84514C (en) Hanging roller wall
CA2123066A1 (en) Glass Run Guide for Slidable Vehicle Window
EP0436191B1 (en) Flexible escalator handrail
HK1011716A1 (en) Polymers having enhanced hydrophilicity and thermal regulated properties and process of producing the same
KR20060127988A (en) Spring element for rail vehicles
US5863029A (en) Swivelably mounted rope guide for guiding a rope onto and off of a winding drum
DE59406439D1 (en) Plastic-coated copper pipe
JP2509416B2 (en) Conductor guide device with roller
JPH01188870A (en) Sliding rail
CN110087514A (en) System for hanging heavy curtain
PL183310B1 (en) Assembly of rollers for a closed-loop cableway
US5649770A (en) Ball circulating structure for linear guide assembly
CA2095877A1 (en) Flexible screw type conveyor system
US5083599A (en) Protective cover device
EP0826901A3 (en) V-belt for high load transmission
JPH1036035A (en) Overlay of elevator guide rail
Kennedy Jr et al. Wear of polyethylene in small-amplitude oscillatory motion
ES2019916B3 (en) TILTED ELEVATOR, ESPECIALLY ELEVATOR OF MATERIAL OR PERSONS.

Legal Events

Date Code Title Description
WAP Application withdrawn, taken to be withdrawn or refused ** after publication under section 16(1)