JPH1029777A - Elevator driving device and elevator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To secure a sufficient friction force by bringing a point facing a side groove into contact with the metal surface of the groove by a particular ratio and a particular contact pressure or higher, the point being selected from ones on a wire constituting the envelope curve of the wire in a rope outermost layer. SOLUTION: While a load of about 1/2 of a rated load is applied in a riding car, the envelope curve 33 of a wire in the outermost layer of a rope is brought into contact within a range exceeding 90% of the inner surface length of the section of a round groove 6. Seeing the impression of the pressure sensitive paper of a rope sieve 4, a point indicates a region where the pressure sensitive paper is pressed to the metal surface of the groove 6 by a pressure of 50MPa or higher. The position of each point corresponds to the position of a point on a wire forming the envelope curve 33 of the rope outermost layer wire. Among points on the wire constituting the envelope curve of the rope surface, a point in the groove side, that is, among points on the wire of the rope outermost layer facing the groove 6 and contacted with the groove 6, at least a point of 90% is in contact therewith by a pressure of 50MPa or higher and thus a contact state is realized in which a good friction factor is obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rope type elevator, and more particularly to a rope groove shape of a sheave for improving traction performance.

[0002]

2. Description of the Related Art A rope type elevator is provided with a driving device including an electric motor, a speed reducer, a sheave, a deflecting wheel and a rope installed at the top of the system, and a rope wound around the sheave provided on the sheave. The mechanism is driven by friction between the car and the car. In order to transmit the driving force efficiently, a high frictional force between the rope and the sheave is required. The frictional force between the rope and the sheave depends on the cross-sectional shape of the groove of the sheave around which the rope is wound, the sheave diameter, and the angle at which the rope is wound around the sheave.

[0003] However, a groove having a U-shaped cross section (hereinafter referred to as a round groove) is excellent in abrasion resistance of the rope sheave, but cannot provide a sufficient frictional force, and may cause slip due to imbalance in tension during acceleration / deceleration. Also occurs. Therefore, in order to increase the frictional force compared to the round groove, an undercut type in which a cut is made in the bottom of a semicircular round groove, a V-groove type in which a groove is cut in a V-shape, and the like are used. On the other hand, the groove width or the groove diameter is set to be larger than the diameter of the rope in order to reduce vibration when the rope is wound. In the case of a semicircular round groove, the diameter is 5% to 6% larger than the cross section of the rope. Processed.

Japanese Patent Laid-Open Publication No. Sho 51-76753 discloses a method for providing an undercut portion in a V-shaped groove in a groove formed in a sheave. Further, a method of making the undercut start point of the groove a convex curved surface is described in Japanese Patent Application Laid-Open No. 60-52073.

However, the prior art does not describe the contact pressure and the area between the rope and the sheave, and does not consider the influence on the friction characteristics.

[0006]

At present, in order to reduce maintenance costs in rope-type elevators, it has been considered to introduce or introduce long-life ropes such as deformed wire ropes, steel core ropes and partial steel core ropes. However, among the shapes of the rope grooves formed on the sheave, if these ropes whose life is to be extended are wrapped around the round groove with the least amount of abrasion of the rope, sufficient driving force may not be obtained depending on the conditions. is there. Therefore, in order to increase the frictional force, when these ropes are used, undercut grooves, V-grooves, etc. are used instead of round grooves. Compared with the round groove, the undercut groove and the V-groove have a large amount of wear on the rope and a short life, so that the initial purpose of these ropes, that is, a long life cannot be achieved. For this reason, it has been an issue to provide a suitable groove shape that ensures a sufficient frictional force and reduces the wear of the rope.

[0007] In order to solve this problem, a contact experiment was carried out on a rope / sheave with an actual load. It was clarified that the influence on the friction characteristics and the wear resistance was obtained.

An object of the present invention is to secure a sufficient frictional force for driving a rope type elevator and extend the life of the rope. It is another object of the present invention to provide an elevator driving device and a rope-type elevator, which secure a sufficient frictional force for driving and have a long rope life.

[0009]

When a rope is wrapped around a sheave and a car and a counterweight are suspended at both ends of the rope, the cross-sectional shape of the rope is deformed by tension. The amount of deformation varies depending on conditions such as the type of core wire, the number of strands, the number of strands, or the shapes of strands and strands generated in the manufacturing process. Even with the same rope diameter, a rope with a small deformation amount comes into local contact with the bottom of the groove, and the friction coefficient decreases.

[0010] The deformed wire rope in which the strands are deformed and adhered to each other by the wire drawing process of the strand has a higher density than the ordinary wire rope and has a smaller deformation amount in the cross-sectional shape. In addition, with regard to steel cores that are long-life ropes and partial steel core ropes, since the core wire, which is a hemp in conventional ropes, is partially or entirely replaced with steel wire, the entire rope is less deformed and the frictional force is reduced. .

For this reason, in the present invention, the clearance between the groove and the rope is minimized, and the rope having a small deformation is brought into contact with the groove as much as possible rather than locally, thereby stabilizing the frictional force. To provide a rope groove shape that can be secured.

In the experiment of contacting the rope and sheave with an actual load, a prescale, a pressure-sensitive paper made by Fuji Film, was used. The contact pressure and the area were measured using FPD-901 manufactured by Fuji Film, which is a prescale image analyzer. In the pressure-sensitive paper, a portion that receives a pressure exceeding a predetermined pressure is discolored. From the experimental results here, the rope type, tension,
The contact state differs depending on the winding angle, and the higher the density of the rope, the smaller the amount of deformation of the cross-sectional shape and the local contact with the groove.

Further, the friction coefficient was measured under the same conditions as in the contact experiment, and the relationship between the contact surface pressure, the area and the friction coefficient was clarified. Here, it was confirmed that the friction coefficient decreased as the surface pressure increased. Furthermore, in order to generate an effective frictional force for driving the elevator in the actual load range, 50M
It was clarified that the wire had to press the sheave groove with a contact pressure of Pa or more.

From the results of these contact experiments and the actual measurement of the coefficient of friction, uniform contact over the entire groove, that is, a stable coefficient of friction,
It has been clarified that forming a groove shape according to the cross-sectional shape of the deformed rope is an effective means to obtain a contact with less wear.

In the present invention, the following configuration is used as the drive device of the rope-type elevator based on the measurement results of the contact experiment with the pressure-sensitive paper and the actual measurement of the friction coefficient in each contact state.

At least 90% of the points on the strands facing the groove during one pitch of the strands among the points on the strands forming the envelope surface of the strand surface have a contact pressure of 50M.
It comes into contact with the metal surface of the groove at a pressure exceeding Pa.
At this time, the tension of the rope is
A tension corresponding to a state where a load of / 2 is applied.

Alternatively, when the rope comes into contact with the groove on the outer peripheral surface of the sheave, among the points on the wire constituting the envelope surface of the strand surface twisted by the wire, the rope is placed on the groove side during one pitch of the strand. At least 90% of the points on the facing strand
Contact the metal surface of the groove with a contact pressure exceeding 50 MPa.

[0018] Alternatively, the envelope of the strand constituting the outermost section of the cross section perpendicular to the rope axis of the rope deformed by the tension load and the pressing force on the sheave is defined by the circumferential direction of the groove formed on the outer peripheral surface of the sheave. Contact with the metal surface of the groove for at least 90% of the inner circumferential length of the groove having a cross section perpendicular to the groove.

Alternatively, at least 90% of the points on the groove side among the points on the strand forming the envelope surface of the rope surface, ie, at least 90% of the points on the strand of the outermost layer of the rope facing the groove and capable of contacting the groove. Point contacts the metal surface of the groove at a pressure exceeding 50 MPa.

At this time, the shape of at least a portion of the cross section of the groove which comes into contact with the rope is a circular arc, and the diameter of the circle having the circular arc as a part of the circumference secures the minimum clearance for the rope to be wound in and the local area. In this case, the diameter is set to a range that does not cause a temporary contact, that is, a range of 101% to 104% of the rope diameter under no load.

Alternatively, at least the portion of the cross section of the groove that contacts the rope is an ellipse whose major axis is arranged in the width direction of the groove, and the major axis of the ellipse is in the range of 101% to 104% of the rope diameter under no load. Is also good.

The start of the rope groove on the sheave circumference is a curved surface,
Alternatively, it is desirable to chamfer with a flat surface.

Further, it is preferable to provide an undercut portion in the groove.

It is effective to combine these groove shapes with a rope having a small cross-sectional deformation particularly under a tension load, that is, a deformed wire rope, a steel core rope, a partial steel core rope, or the like.

The following effects can be obtained by using the above means. According to the above-described configuration, the rope does not only locally contact the groove bottom but also contacts the groove side surface, so that the surface pressure is low and a stable frictional force can be obtained.
In other words, the contact area between the rope and the sheave was increased by forming the same shape as the cross-sectional shape of the rope deformed by the pressing force against the sheave due to the tension at the time of load, thereby ensuring a sufficient frictional force. .

Further, by using a groove having a diameter smaller than that of the conventional round groove, a stable frictional force can be similarly secured with respect to the rope having a small deformation amount. Alternatively, by forming an elliptical groove shape on the sheave that conforms to the rope cross-sectional shape deformed by being pressed against the sheave, the entire groove can be used as a contact area with the rope, and the frictional force increases. When further frictional force is required, by providing an undercut portion in the groove, the edge effect at the start point of the undercut portion contributes to an increase in the frictional force in addition to a large contact area. At this time, the contact area on the side surface of the groove is larger and the load concentrated on the edge portion is reduced as compared with the conventional groove in which the undercut portion is provided in the round groove, so that the amount of wear can be reduced. In addition, by chamfering the start portion of the rope groove on the sheave circumference with a curved surface or a flat surface, the rope is smoothly wound into the groove during operation, and vibration when the rope is wound into a narrower groove is reduced. .

[0027]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention is shown in FIGS.
7 will be described. FIG. 11 is a schematic view of an elevator according to the present invention. The elevator shown is a sheave 4,
A deflecting wheel 5 whose rotation axis is parallel to the rotation axis of the sheave 4 and which is separated from the sheave 4 by a predetermined distance; a rope 3 wound around the sheave 4 and the deflecting wheel 5; It comprises a car 1, a counterweight 2 suspended from the other end of the rope 3, and an electric motor and a speed reducer (not shown) for driving the sheave 4.

A drive device including a motor, a speed reducer, a sheave 4, and a deflector wheel 5, which are omitted in the drawing, sheaves a rope 3 wound around a rope groove (hereinafter referred to as a groove) formed in the sheave 4. Driven by the rotation of 4 and the basket 1
Up and down.

FIG. 12 shows the rope 31 wound around the groove 6 provided on the outer peripheral surface of the sheave 4 and under tension.
3 is a schematic cross-sectional view using the envelope 33 of the outermost element wire. At this time, the rope loses its shape from a perfect circle and deforms due to the pressing force against the sheave due to the tension and the winding. In the figure, dw1 indicates the diameter of the cross section of the rope 31 after deformation in the direction parallel to the sheave rotation axis, and dH indicates the diameter of the rope 31 in the direction perpendicular to the sheave rotation axis. Expressed by When a load is applied by being wound around the sheave 4, the rope 3 is deformed, dw1 increases, and dH decreases, so that the oblateness increases. Note that d
In FIG. 11, w1 and dH are values at the central portion E of the region where the rope 3 is wound around the sheave 4.

FIG. 13 shows various ropes.
Shows a cross section of a normal wire rope 7, (b) shows a cross section of a deformed wire rope 8, and (c) shows a cross section of a steel core rope 9, respectively. The deformed wire rope 8 that is further subjected to wire drawing on a strand formed of a plurality of drawn wires has a changed shape. Therefore, unlike the ordinary wire rope 7, the strands are in close contact with each other and have a high density, and since they are in contact with each other, there is little deformation. In addition, since the steel core rope 9 uses not only hemp but also a steel core, the core wire is less likely to lose its shape.

FIG. 14 shows a deformed wire rope 8 and a normal wire rope 7.
And a change in oblateness due to a change in tension of the steel core rope 9. Since the deformed line rope 8 has a high density and a small deformation, the oblateness is smaller than that of the ordinary line rope 7.

FIG. 15 shows the relationship between the contact area and the oblateness measured by Fuji Film's pressure-sensitive paper prescale and its image analyzer FPD-901, using tension as a parameter. Since the deformed wire rope 8 having a low flattening rate contacts the groove locally, the contact area between the rope and the sheave is smaller than that of the ordinary wire rope 7.

FIG. 16 shows an ordinary wire rope 7 and a deformed wire rope 8.
And a change in the contact area between the rope and the groove 6 when a tension is applied to the steel core rope 9. When the tension is low, the contact area of the irregularly shaped wire rope 8 whose surface is smooth is larger than that of the ordinary wire rope 7 or the steel core rope 9, but in the practical tension range used for elevators, the ordinary wire rope 7 loses its shape. In reverse, the contact area of the deformed wire rope 8 becomes smaller than that of the ordinary wire rope 7.

FIG. 17 is a conceptual diagram showing a conventional contact between a rope and a round groove. The figure shows a cross section of the rope using the envelope of the outermost layer of the rope. In the drawing, dw2 indicates the diameter of the rope 32 (diameter of the envelope) when no load is applied, and D indicates the diameter of the groove 6. Here, the groove diameter D is not the width of the starting point of the groove 6 formed on the outer peripheral surface of the sheave 4 (the width on the outer peripheral surface), but the diameter of a circle having the cross section of the groove 6 as a part of the circumference. . When the deformed wire rope 8 having a low flatness is used, the clearance δ is large, so that the rope locally comes into contact with the bottom of the groove 6 and a stable frictional force cannot be obtained.

FIG. 1 shows a first embodiment of the present invention. The figure shows a cross section of the rope and the groove in a plane including the sheave rotation axis at the position E in FIG. 11, and LR in the figure shows that the envelope 33 of the outermost element wire of the rope crosses the metal surface of the groove inner surface. LS indicates the length of the inner surface of the groove in the groove cross section. In the present embodiment, a state is shown in which tension is applied to the car with a load of 定 格 of the rated load being applied, and the envelope 33 of the outermost strand of the rope is the inner surface of the cross section of the round groove 6. Contacting more than 90% of the length.

FIG. 2 shows the relationship between the maximum contact pressure of the wire indentation measured in the contact test and the friction coefficient actually measured under the same conditions. In the figure, LT indicates the minimum driving force for driving the actual elevator. To drive the elevator, a contact pressure of 50 MPa or more is required.

FIG. 3 shows that the points on the strands forming the envelope surface of the strand surface on the strands facing the groove during one pitch of the strands have a contact pressure of 50 MPa.
The coefficient of friction changes depending on the number of contact points above a. In the figure, Nt indicates the number of element wires facing the groove inner surface during one pitch of the strand in the rope sheave contact test, and Nc indicates the number of contact points of the element wires in contact with the sheave groove at 50 MPa or more. . FIG. 3 shows that the coefficient of friction changes depending on the number of contact points of the strands per one pitch of the strand.
When c / Nt is less than 0.9, it indicates that the decrease in the coefficient of friction is large.

FIG. 4 shows the coefficient of friction that varies depending on the ratio of the length of contact of the outermost layer of the rope with the envelope to the arc length of the groove cross section. The friction coefficient is stable when the envelope of the wire contacts the entire arc length of the groove cross section, but when the contact becomes less than 90% of the arc length of the groove cross section where local partial contact starts to occur, it suddenly becomes sharp. It is shown that the friction coefficient decreases.

FIG. 5 shows the impressions of the pressure-sensitive paper when a rope / sheave contact experiment was performed in a groove shape based on the embodiment of the present invention. The pressure-sensitive paper used was capable of measuring 50 to 130 MPa. The rope tension was such that a half of the rated load was applied to the car. The point in the figure is 5
The area where the pressure-sensitive paper is pressed against the metal surface of the groove with a pressure of 0 MPa or more is shown, and the position of each point corresponds to the position of a point on the wire forming the envelope surface of the outermost layer wire of the rope. . In the illustrated area, of the points on the strand forming the envelope surface of the rope surface, the point on the groove side, that is, the point (54 points) on the strand of the outermost layer of the rope that faces the groove and can contact the groove is shown. At least 90% of the points are in contact with each other at 50 MPa or more, indicating that the contact state is such that a good friction coefficient is obtained. This indicates that the car has 1 /
When a load of 2 is applied, a good coefficient of friction can be obtained if at least 90% of the points on the strands of the outermost layer of the rope that can face and contact the groove are in contact with the groove. confirmed.

FIG. 6 shows a second embodiment of the present invention. FIG.
Shows a cross section similar to FIG. In this embodiment,
The diameter D of the round groove 6 is 101% of the rope diameter dw2 when no load is applied.
Not less than 104% or less, that is, 1.01 ≦ D / d
It is formed in the range of w2 ≦ 1.04. As a result of setting the diameter D of the round groove 6 to a value within this range, the rope was pressed not only on the groove bottom but also on the groove side surface, so that a low surface pressure as a whole and a stable frictional force could be obtained.

Since the rope to which tension is applied has a smaller diameter than when no load is applied, it is possible to wind the rope 6 into a narrower groove 6 than in the prior art. Further, since the rope 3 is pressed against the sheave 4 and deformed while the sheave 4 is rotating, a pressing force is generated not only on the bottom of the groove 6 but also on the side surface, and the frictional force increases.

FIG. 7 shows the change in the friction coefficient with the rope diameter dw1 (the diameter in the direction parallel to the sheave rotation axis, in other words, the diameter in the groove width direction) as the groove diameter D increases. When the diameter of the rope groove 6 of the sheave 4 becomes larger than the diameter of the rope, only a part of the surface of the groove 6 comes into contact with the rope 3, so that the contact surface pressure increases. In general, as the contact surface pressure increases, the coefficient of friction tends to decrease, and the friction between the rope and the sheave is no exception. Also in FIG. 7, the ratio of the groove diameter D / the rope diameter dw1 is 1.04.
It is shown that the friction coefficient is significantly reduced when the ratio exceeds. For this reason, when using a rope with a small amount of deformation, a groove shape for increasing the contact area is required. In particular, for deformed ropes, steel core ropes that use a steel core without using hemp for the core wire, and partial steel core ropes that include a steel core in the hemp core,
It is desirable that the value of / dw2 be 1.04 or less, that is, the diameter of the groove 6 be 104% or less of the rope diameter under no load. On the other hand, if the diameter of the groove 6 is too small, it becomes difficult to wind the rope into the sheave, causing vibration or abrasion. Therefore, the diameter of the groove 6 is one of the rope diameter under no load.
Desirably, the range is at least 01%.

FIG. 8 shows a groove shape according to a third embodiment of the present invention. When tension is applied to the rope and the rope is pressed against the sheave, the cross-sectional shape of the rope changes. For this reason, in this embodiment, the cross-sectional shape of the groove 6 includes a part of the circumference of the ellipse, and the major axis of the ellipse is one of the rope cross-sectional diameter at no load.
It is processed so as to be in a range of 01% or more and 104% or less, the contact area between the rope and the sheave is large, and a stable frictional force can be secured.

FIG. 9 shows a fourth embodiment of the present invention. However, the cross-section of the rope without load is shown in the figure for comparison. In this embodiment, the groove start portion on the sheave circumference (upper end in the width direction of the groove)
Is chamfered by the plane 10. A chamfer with a curved surface may be used instead of a chamfer with a flat surface. Since the groove start portion of the sheave surface is chamfered by a curved surface or a flat surface 9, the riding comfort is reduced due to less impact when the rope is wound in during operation and when the rope is separated. As in the above embodiment, the diameter of a circle having the cross section of the groove 6 as a part of the circumference is in the range of 101% or more and 104% or less of the rope cross-section diameter under no load, so that the contact area is large and stable. A friction force is obtained.

FIG. 10 shows a fifth embodiment of the present invention. In the figure, the rope cross section at the time of no load is shown for comparison. In this embodiment, an undercut portion is provided at the bottom of the round groove of the sheave of the embodiment shown in FIG. By providing the undercut portion, a reliable frictional force can be obtained even in a single wrap where the rope is wound around the sheave only once.

In order to confirm the accuracy of the groove shape after the manufacture of the sheave, it is desirable to confirm the contact state with pressure-sensitive paper.

The present invention relates to a rope having a small deformation when the rope is wound around the sheave, that is, a partially steel core rope in which a part of the core wire is a steel wire,
This is particularly effective for steel core ropes whose core portion is only a steel wire.

[0048]

According to the present invention, when a deformed wire rope having a small shape loss is used, a reduction in frictional force due to a reduction in the contact area between the rope and the sheave is eliminated, and a stable driving force can be obtained.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a first embodiment of the present invention.

FIG. 2 is a conceptual diagram showing a relationship between a contact pressure of a strand between a rope and a sheave and a friction driving force.

FIG. 3 is a conceptual diagram showing a relationship between a ratio of a wire in contact with a sheave metal surface at a contact pressure of 50 MPa or more and a friction coefficient.

FIG. 4 is a conceptual diagram illustrating a relationship between a contact state between a rope and a sheave and a friction coefficient.

FIG. 5 is a developed view showing a contact state between a rope and a sheave actually measured with pressure-sensitive paper.

FIG. 6 is a sectional view showing a second embodiment of the present invention.

FIG. 7 is a conceptual diagram showing the relationship between groove diameter / rope diameter and friction coefficient.

FIG. 8 is a sectional view showing a third embodiment of the present invention.

FIG. 9 is a sectional view showing a fourth embodiment of the present invention.

FIG. 10 is a sectional view showing a fifth embodiment of the present invention.

FIG. 11 is a schematic configuration diagram illustrating an example of an elevator including an elevator driving device.

FIG. 12 is a sectional view showing a relationship between a groove of a sheave and a rope.

FIG. 13 is a diagram showing a cross-sectional shape of various ropes.

FIG. 14 is a conceptual diagram showing the relationship between the magnitude of tension and the flattening ratio when various ropes are wound around sheaves and flattened by applying tension.

FIG. 15 is a conceptual diagram showing the relationship between the oblateness and the contact area of various ropes, using the tension applied to the rope as a parameter.

FIG. 16 is a conceptual diagram showing a relationship between tensions of various ropes and contact areas.

FIG. 17 is a cross-sectional view showing a relationship between a conventional rope and a groove of a sheave.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Riding car 2 Counterweight 3 Rope 4 Sheave 5 Deflection car 6 Sheave rope groove 7 Normal line rope 8 Deformed line rope 9 Steel core rope 10 Rope groove start point 11 Undercut part 31 Rope deformed by tension etc. 32 No load Rope 33 Envelope of the outermost layer of the rope

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Eiichi Sasaki, Inventor 1070 Ma, Hitachinaka-shi, Ibaraki Pref. Hitachi, Ltd. Mito Plant

Claims (11)

[Claims] 1. A rope having a car connected to one end thereof and a counterweight connected to the other end thereof, and a metal sheave wound around the rope and driven by friction, wherein the rope comprises a plurality of strands. In the elevator drive device configured by twisting the strand formed by twisting, when the rope comes into contact with a groove formed on the outer peripheral surface of the sheave and around which the rope is wound, an envelope surface of the strand surface is formed. At least 90% of the points on the strands facing the groove during one pitch of the strand of the constituent strands contact the metal surface of the groove with a contact pressure exceeding 50 MPa. And elevator drive. 2. A rope having a car connected to one end and a counterweight connected to the other end, and a metal sheave wound around the rope and frictionally driven, wherein the rope comprises a plurality of strands. In an elevator drive device configured by twisting twisted strands, when the rope is deformed by a tensile load and a pressing force against the sheave, each strand having a cross section perpendicular to the rope axis is formed. Of the strands, the envelope connecting the strand farthest from the center of the rope is formed on the outer peripheral surface of the sheave, and the groove surface length in a cross section perpendicular to the sheave circumferential direction of the groove around which the rope is wound. An elevator drive contacting the metal surface of the groove for at least 90% of its range. 3. A rope having a car connected to one end and a counterweight connected to the other end, and a metal sheave wound around the rope and driven by friction, wherein the rope comprises a plurality of strands. In an elevator drive device configured by twisting a twisted strand, a point facing a groove formed on an outer peripheral surface of the sheave, among points on a wire constituting an envelope of the surface of the rope. Wherein at least 90% of the contact is in contact with the metal surface of the groove with a contact pressure exceeding 50 MPa. 4. A rope having a car connected to one end and a counterweight connected to the other end, and a metal sheave wound around the rope and driven by friction, wherein the rope comprises a plurality of strands. In the elevator drive device configured by twisting the twisted strands, a groove formed on the outer peripheral surface of the sheave and around which the rope is wound is a circular groove, that is, a cut in a plane including the sheave rotation axis. The shape of at least the metal part of the cross section of the surface that contacts the rope is a circular arc, and the diameter of the circle including the circular arc is 101% to 10% of the cross sectional diameter of the rope when no load is applied.
An elevator driving device characterized by being in the range of 4%. 5. A rope having a car connected to one end and a counterweight connected to the other end, and a metal sheave wound around the rope and driven by friction, wherein the rope comprises a plurality of strands. In the elevator drive device configured by twisting the twisted strands, the groove around which the rope formed on the outer peripheral surface of the sheave is wound is an elliptical groove, that is, a cut surface in a plane including the sheave rotation axis. At least the shape of the metal part of the cross section of the section abutting on the rope includes a part of the circumference of the ellipse, and the major axis of the ellipse is in the range of 101% to 104% of the rope cross-sectional diameter at no load. And elevator drive. 6. The elevator drive device according to claim 1, wherein an undercut portion is provided at a bottom of the rope groove of the sheave. 7. The elevator driving device according to claim 1, wherein the rope groove formation start portion is chamfered by a curved surface or a flat surface over the entire circumference of the sheave circumference. Elevator drive. 8. The elevator driving device according to claim 1, wherein the rope is a normal wire rope that has not been subjected to a wire drawing process using a die for a strand. Drive. 9. The elevator drive device according to claim 1, wherein the rope is subjected to a wire drawing process using a die on a strand, and a deformed wire rope having a smooth strand surface is used. An elevator driving device characterized by the above-mentioned. 10. The elevator driving device according to claim 1, wherein a steel core rope having a core wire including a steel wire is used as the rope. 11. A rope type elevator comprising a car, a counterweight, a safety device, an elevator driving device, and a control device, wherein the elevator driving device is the elevator driving device according to any one of claims 1 to 10. A rope-type elevator characterized by the following.