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         metrically relative to the vertical center line passing via the
         center of gravity of the elevator car 1. A preferable solution is
         to dispose the traction sheave 7 and the diverting pulley 15 in
         such a way that the diverting pulley 15 will also function as a
         guide of the hoisting ropes 3 and as a damping pulley.
           Figure 2 presents a diagram representing another traction
         sheave elevator according to the invention. In this elevator,
         the ropes go upward from the machine. This type of elevator
         is generally a traction sheave elevator with machine below.
         The  elevator car  101 and the  counterweight  102 are sus-
         pended on the hoisting ropes 103 of the elevator. The eleva-
         tor drive machine unit 106 is mounted in the elevator shaft,
         preferably in the lower part of the shaft, a diverting pulley
         115 is mounted near the drive machine unit 106, said divert-
         ing pulley allowing a sufficiently large contact angle to be
                                                              Figure 4: Steel wire rope used in the invention.
                                                              the traction sheave and the rope pulleys may consist of rub-
                                                              ber, polyurethane, or a corresponding elastic material that
                                                              increases friction. The material of the traction sheave and/
                                                              or rope pulleys may also be so chosen that, together with
                                                              the hoisting rope used, it forms a material pair such that
                                                              the hoisting rope will bite into the pulley after the coating
                                                              on the pulley has been worn out. This ensures a sufficient
                                                              grip between  the rope pulley  200 and the hoisting  rope  3
                                                              in an emergency where the coating 202 has been worn out
                                                              from the rope pulley 200. This feature allows the elevator to
                                                              maintain its functionality and operational reliability in the
                                                              situation referred to.
                                                               The  traction  sheave  and/or  the  rope  pulleys  can  also  be
                                                              manufactured  in  such  manner  that only  the  rim  206  of
                                                              the rope pulley 200 is made of a material forming a grip-
                                                              increasing material pair with the hoisting rope 3. The use
                                                              of strong hoisting ropes that are considerably thinner than
                                                              normal allows the traction sheave and the rope pulleys to be
                                                              designed to considerably smaller dimensions and sizes than
                                                              when normal-sized ropes are used. This also makes it pos-
                                                              sible to use a motor of a smaller size with a lower torque as
                                                              the drive motor of the elevator, which leads to a reduction in
                                                              the acquisition costs of the motor. For example, in an eleva-
                                                              tor according to the invention designed for a nominal load
                                                              below 1000 kg (e.g., a rated load below 1000 kg), the traction
                                                              sheave diameter is preferably 120-200 mm, but it may even
                                                              be less than this. The traction sheave diameter depends on
                                                              the thickness of the hoisting ropes used. In the elevator of
                                                              the invention, the use of a small traction sheave, e.g. in the
         Figure 3: Rope sheave applying the invention.        case of elevators for a nominal load below 1000 kg, makes it

         achieved between the traction sheave 107 and the hoisting
         ropes 103. The hoisting ropes are passed via diverting pul-
         leys 104, 105 provided in the upper part of the elevator shaft
         to the car 101 and to the counterweight 102. Diverting pul-
         leys 104, 105 are placed in the upper part of the shaft and
         preferably separately mounted with bearings on the same
         axle so that they can rotate independently of each other.
           Figure 3 presents a partially sectioned view of a rope pul-
         ley 200 applying the invention. The rim 206 of the rope pul-
         ley is provided with rope grooves 201, which are covered by
         a coating 202. Provided in the hub of the rope pulley is a
         space 203 for a bearing used to mount the rope pulley. The
         rope pulley is also provided with holes 205 for bolts, allow-
         ing the rope pulley to be fastened by its side to an anchorage
         in the hoisting machine 6, e.g., to a rotating flange, to form
         a traction sheave 7, so that no bearing separate from the
         hoisting machine is needed. The coating material used on
                                                              Figure 5: Another steel wire rope used in the invention.
         50     Wire Rope News & Sling Technology   February 2017
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