ELEVATOR ROLLER FOR AN ELEVATOR SYSTEM, ELEVATOR SYSTEM HAVING AT LEAST ONE SUCH ELEVATOR ROLLER, AND METHOD FOR PRODUCING AN ELEVATOR ROLLER

Abstract

A roller for an elevator system has a roller body made of a metal material and a shell made of a POM material forming a running surface of the elevator roller. The shell and the roller body each have a wave profile running in a circumferential direction on a shared contact surface, wherein the shell has, on the running surface, a V-ribbed profile aligned with the wave profile of the roller body that has a rib spacing which substantially corresponds to a wave spacing of the wave profile. The elevator roller is manufactured using a molding process.

Claims

1-15. (canceled)

16. An elevator roller for an elevator system, the elevator roller comprising: a roller body made of a metal material; a shell made of a POM material and forming a running surface ending in a circumferential direction about an outer surface of the elevator roller; wherein the shell and the roller body each have a wave profile running in the circumferential direction on a shared contact surface; and wherein the shell has, on the running surface, a V-ribbed profile aligned with the wave profile of the roller body, the V-ribbed profile having a rib spacing that corresponds to a wave spacing of the wave profile of the roller body.

17. The elevator roller according to claim 16 wherein the shell has a material thickness between 1 mm and 5 mm in a region of the running surface.

18. The elevator roller according to claim 17 wherein the material thickness varies by less than 30% at different positions along a longitudinal direction of the shell.

19. The elevator roller according to claim 16 wherein the POM material has a material coefficient of friction between 0.1 and 0.6 with respect to a PU material of an elevator suspension belt engaging the running surface.

20. The elevator roller according to claim 16 wherein the wave profile of the roller body has peaks running in the circumferential direction and valleys running in the circumferential direction between the peaks, wherein peak radii of the peaks are smaller than valley radii of the valleys.

21. The elevator roller according to claim 16 wherein an extrusion surface of the POM material is unprocessed at least in a region of the running surface.

22. The elevator roller according to claim 16 wherein the shell has at least one edge disk made of the POM material and laterally adjoining the running surface.

23. The elevator roller according to claim 22 wherein an extrusion surface of the POM material is unmachined at least in a region of an inside surface of the edge disk facing the running surface.

24. The elevator roller according to claim 16 wherein an outer ring of a bearing forms the roller body, the outer ring having the wave profile of the roller body.

25. The elevator roller according to claim 24 wherein the bearing is a sealed, double-row ball bearing in an O arrangement.

26. The elevator roller according to claim 16 including a bearing and wherein the roller body has a fitting surface receiving an outer ring of the bearing on a side opposite the contact surface.

27. The elevator roller according to claim 26 wherein the bearing is a sealed, double-row ball bearing in an O arrangement.

28. An elevator system comprising:

16. one elevator roller according to claim 16; and a belt having a V-ribbed surface made of a PU material guided in the circumferential direction over the running surface of the at least one elevator roller.

29. A method for manufacturing an elevator roller for an elevator system, the method comprising the steps of: forming a shell of a POM material with a running surface; connecting the shell to a roller body made of a metal material at a common contact surface to form the elevator roller; wherein the contact surface has a wave profile running in a circumferential direction of the elevator roller; and wherein the shell has a V-ribbed profile running in the circumferential direction on the running surface, the V-ribbed profile having ribs at a rib spacing corresponding to a wave spacing of the wave profile.

30. The method according to claim 29 wherein the step of connecting includes injection molding the shell onto the roller body using an injection molding process, wherein the contact surface wave profile includes a wave profile of the shell that is complementary to a wave profile of the roller body, and including forming the V-ribbed profile of the running surface an injection molding tool used in the injection molding process.

31. The method according to claim 30 including injection molding at least one edge disk of the shell onto the roller body with an outward inclination, wherein the inclination is compensated during a cooling phase after removal of the elevator roller from the injection molding tool due to thermal shrinkage of the shell.

Description

DESCRIPTION OF THE DRAWINGS

[0033] FIG. 1 shows an illustration of an elevator system having at least one elevator roller according to an embodiment;

[0034] FIG. 2a shows a cutaway illustration of an elevator roller according to an embodiment;

[0035] FIG. 2b shows a detailed illustration of a V-ribbed profile of an elevator roller, aligned with a wave profile, according to an embodiment illustrated in detail A of FIG. 2a; and

[0036] FIG. 3 shows a cutaway illustration of a multi-part elevator roller according to an embodiment.

[0037] The drawings are merely schematic and not to scale. Like reference signs refer to like or equivalent features in the drawings.

DETAILED DESCRIPTION

[0038] FIG. 1 is an illustration of an elevator system 100 having at least two elevator rollers 102 according to an embodiment of the invention. The elevator rollers 102 can be referred to as pulleys of the elevator system 100. The elevator system 100 has a car 104 which is suspended in an elevator shaft 106 on one or more belts 108 so that it can move vertically. Guide rails for guiding the car 104 in the elevator shaft 106 are not shown here for the sake of simplicity.

[0039] The elevator rollers 102 are arranged in the region of a base of the car 104, and the belt 108 runs over the elevator rollers 102. The belt 108 connects the car 104 to a drive 110 of the elevator system 100 and to a counterweight 112 of the elevator system 100. The belt 108 is fastened at each end to a fixed point 114 of the elevator shaft 106. The fixed points 114 are arranged in an upper end region of the elevator shaft 106.

[0040] The belt 108 runs vertically downward from one of the fixed points 114 on one side of the car 104 to one of the elevator rollers 102. The elevator roller 102 is arranged in a lateral lower corner region of the car 104. Over the elevator roller 102, the belt 108 is deflected to the horizontal and runs horizontally under the car 104 through to the other elevator roller 102. The other elevator roller 102 is arranged in an opposite lateral lower corner region of the car 104. Over the other elevator roller 102, the belt 108 is deflected back to the vertical, and runs vertically on the other side of the car 104 upward to a drive roller of the drive 110. The belt 108 is deflected by 180° over the drive roller and runs vertically downward to a deflection roller 116 connected to the counterweight 112. Over the deflection roller 116, the belt 108 is deflected again by 180°, and again runs vertically upward to the other fixed point 114.

[0041] The belt 108 in this case is a V-ribbed belt with at least one V-ribbed surface. Therefore, at least the elevator rollers 102 have a V-ribbed profile on a running surface. Due to the V-ribbed surface engaging in the V-ribbed profile, the belt 108 is guided laterally in the elevator rollers 102—that is, in an axial direction of the elevator rollers 102 and thus transversely to a longitudinal direction of the V-ribbed profile. The elevator rollers 102 have edge disks as an additional lateral guide.

[0042] FIGS. 2a and 2b show a cutaway view of an elevator roller 102 according to an embodiment. FIG. 2a shows a cutaway view of the entire elevator roller. FIG. 2b shows an enlarged illustration of the detail A of the cutaway illustration in FIG. 2a. The elevator roller 102 corresponds substantially to one of the elevator rollers in FIG. 1. The elevator roller 102 is shown cut in the middle along an axis of rotation.

[0043] The elevator roller 102 has a roller body 200 and a shell 202. The shell 202 forms a running surface 204 of the elevator roller 102. The roller body 200 consists of a metal material, in particular steel. The shell 202 is made of a POM material. A polyoxymethylene material is what is referred to as a POM material. A contact surface 206 between the shell 202 and the roller body 200 has a wave profile in some regions in a circumferential direction of the elevator roller 102. The roller body 200 thus has a positive wave profile 208, while the shell 202 has an identical and complementary negative wave profile 210.

[0044] In one embodiment, the POM material is referred to as PAS-L material, in particular PAS-L69. Such a POM material is produced by Faigle (based in Hard, Austria). Information on this POM material is available at www.faigle.com, in particular at www.faigle.com/presse/die-pas-l-materialfamilie/. A density of such POM material can be about 1.41 g/cm.sup.3. A maximum permissible compressive load (permanent) can be 16 N/mm.sup.2 (static). The pv value, i.e. the product of the specific pressure (p) and the surface velocity (v), determines the usability of the material. Both influencing factors interact with each other. Depending on the surface speed, the value during dry running against steel can be between 0.1 and 0.15. A dynamic coefficient of friction is, for example, 0.3, this value being an average value for dry running on steel.

[0045] The POM material is injection molded onto the roller body 200 to produce the elevator roller 102. For this purpose, the roller body 200 is arranged in a receptacle of an injection molding tool for producing the shell 202. By closing the injection molding tool, a mold cavity for the shell 202 is formed. The POM material is injected into the mold cavity in plasticized form, acquires its shape, and bonds with the contact surface 206. The plasticized POM material can be injected into the mold cavity through at least three evenly distributed sprues. Alternatively, the POM material can be injected into the mold cavity via an annular diaphragm gate. After the mold cavity has been completely filled, the POM material cools below a plasticizing temperature and solidifies in the mold cavity. After solidification, the injection molding tool is opened and the elevator roller 102 is removed. The POM material continues to cool down after being removed and thus achieves its desired properties.

[0046] The positive wave profile 208 of the roller body 200 has peaks 212 and valleys 214. The peaks 212 of the positive wave profile 208 have a smaller peak radius than a valley radius of the valleys 214 of the positive wave profile 208. Peak radii and valley radii transition directly into each other. Correspondingly, the complementary negative wave profile 210 of the shell 202 also has peaks 215 and valleys 213, the peaks 215 of the negative wave profile 210 each having a peak radius corresponding to the valley radius of the positive wave profile 208, and the valleys 213 of the negative wave profile 210 each having a peak radius corresponding to the valley radius of the positive wave profile 208. The peaks 215 of the negative wave profile 210 therefore have a greater peak radius than the valley radius of the valleys 213 of the negative wave profile 210.

[0047] The positive wave profile 208 of the roller body 200 has six valleys 214 and five peaks 212 in this case. The outer valleys 214 each terminate in an unprofiled shoulder region 216 of the roller body 200.

[0048] The shell 202 has a V-ribbed profile 218 on the running surface 204. The V-ribbed profile 218 has five ribs 220. The ribs 220 are aligned in the radial direction with the peaks 212 of the positive wave profile 208 of the roller body 200. A rib spacing 222 between two ribs 220 of the V-ribbed profile 218 is, within a processing tolerance, equal to a wave spacing 224 between two peaks 212 of the wave profile 208. The V-ribbed profile 218 provides a lateral guide for the belt, which is accordingly configured with V-ribs.

[0049] In one embodiment, the wave spacing 224 and the rib spacing 222 are five millimeters. However, the spacing between the ribs can also be larger or smaller. For example, the rib spacing can be in a range from 1 mm to 20 mm.

[0050] Due to the alignment of the V-ribbed profile 218 with the positive wave profile 208, the shell 202 has a substantially constant material thickness in the cutaway plane shown.

[0051] In one embodiment, the elevator roller 102 has edge disks 226. The edge disks 226 laterally delimit the running surface 204 in order to reliably prevent the belt from escaping laterally. The peripheral disks 226 terminate in a narrow shoulder. The V-ribbed profile 218 adjoins the shoulder.

[0052] In order to make post-processing of the edge disks 226 unnecessary, the edge disks are correspondingly injected with a forward inclination during the injection molding process—that is, for example, they are injection molded with an outward inclination. The thermal shrinkage of the POM material from a solidification temperature to room temperature compensates for the inclination when it cools. The forward inclination is incorporated into the injection molding tool.

[0053] In one embodiment, the flanks of the ribs 220 have an angle of 45°. A rib head of the ribs 220 is rounded, with a radius of 0.9 millimeters. At the rib head, the shell 202 has a material thickness of 3.5 millimeters. A rounded groove 228 is arranged at a rib base of the ribs 220. The groove 228 is rounded with radii of 0.5 millimeters.

[0054] In one embodiment, the peaks 212 of the positive wave profile 208 have a radius of one millimeter. The valleys 214 of the positive wave profile 208 have a radius of 1.85 millimeters.

[0055] In one embodiment (see FIG. 2a), an outer ring 230 of a bearing 232 of the elevator roller forms the roller body 200. The positive wave profile 208 is formed directly in the outer ring 230. This embodiment corresponds to a two-part embodiment. The bearing 232 with the outer ring 230 forms the first part. The shell 202 forms the second part.

[0056] As an alternative to this, in one embodiment the roller body 200 has an inner cylindrical recess into which one or more bearings 232 of the elevator roller 102 are pressed.

[0057] In one embodiment, the bearing 232 is a roller bearing. In this case, the bearing 232 is configured as a two-row ball bearing in an O arrangement. A gap between the outer ring 230 and an inner ring 234 of the bearing 232 is sealed off.

[0058] FIG. 3 shows a cutaway illustration of a multi-part elevator roller 102 according to an embodiment. The elevator roller 102 corresponds substantially to the elevator roller illustrated in FIG. 2a. The shell 202 and the roller body 200 are permanently fixed to each other, as in FIG. 2a. In contrast to the illustration in FIG. 2a, the elevator roller 102 shown in FIG. 3 has a larger diameter in this case. As a result, the roller body 200 has a sufficient wall thickness to allow pressing a conventional bearing 232 into it. For this purpose, the roller body 200 has an internal, substantially cylindrical recess into which one or more bearings 232 of the elevator roller 102 are pressed with the outer ring 230 being received against a fitting surface 236 opposite the contact surface 206.

[0059] The outer ring 230 of the bearing 232 adjoins the roller body 200 directly via a press fit. This embodiment of the elevator roller 102 corresponds to a three-part embodiment. The bearing 232 with the outer ring 230 forms the first part. In contrast to the two-part embodiment, the three-part embodiment also has a separate roller body 200 that is not embodied on the outer ring 230 of the bearing 232. In this embodiment, the roller body 200 is configured as a type of mantle. The shell 202 forms the third part. In one embodiment, the outer ring 230 of the bearing 232 is additionally fixed in the axial direction by a collar 300 running around the recess in the circumferential direction, and a snap ring 304 inserted in a groove 302 running around the recess in the circumferential direction.

[0060] In one embodiment, the running surface 204 has a smaller width x than in FIG. 2a. The V-ribbed profile 218 has the same rib spacing as in FIG. 2a. Therefore, the elevator roller in this embodiment has only three ribs. The roller body 200, however, has the same width as in FIG. 2a. The edge disks 226 are therefore wider than implemented in FIG. 2a in order to compensate for the difference in width between the running surface 204 and the roller body 200. However, as in FIG. 2a, the positive wave profile 208 of the roller body 200 has five peaks and substantially the same wave spacing. The two outermost valleys of the positive wave profile 208 therefore lie outside the running surface 204. The width x can be varied to x′ within a variance 306 by adapting the injection molding tool.

[0061] Finally, possible configurations of the elevator roller proposed here are explained again with a slightly different choice of words.

[0062] A pulley with a plastic coating is presented. High molecular polyoxymethylene (POM) is used for the coating. In combination with a belt made of polyurethane (PU) material, the material coefficient of friction is between 0.1 and 0.6. The material coefficient of friction with respect to PU material is substantially independent of the contact pressure, temperature and humidity. The contact pressure with respect to PU material of the belt is 0.8 N/mm.sup.2 to 5.0 N/mm.sup.2; the coating can be used at temperatures between 5-40° C., and even at temperatures between −5 to 60° C., without any problems. The humidity can be up to 95% RH. There is little or no electrostatic charge with PU material. The POM material has high ductility down to −40° C., and excellent wear resistance. Furthermore, the POM material has good running properties, high impact resistance, and strength over a wide temperature range. The ductility results in resistance to repeated impact loads. The POM material has very good temperature resistance and exceptional dimensional stability. Furthermore, the POM material has long-term creep resistance and high flexural fatigue strength. The POM material also has excellent resistance to moisture, chemicals and fuels. The POM material can be processed by injection molding and extrusion and is suitable for 2K injection molding.

[0063] Two or more pulleys with different diameters (between D85 mm and D147 mm), for example D95, D105, D110, D125, can be produced. With the larger pulleys, a three-part structure consisting of a steel ring with a plastics material running surface and a bearing is used to achieve the diameter. This means that the same roller bearing can also be used for the larger pulleys. The same roller bearing can be used for different belt widths; only the plastics material external geometry is varied for this. This has the advantage that the variance in the roller bearings is not present, or is at least very small—that is to say that the same roller bearing can be used with a plurality of pulley diameters. In this way, the number of roller bearing types can be kept small, and the expenses for retooling in the production process, and the space requirements and costs for storage can be significantly reduced. During injection molding, pressures of up to 600 bar can occur. Due to the high pressure and the high temperature, the roller body is stressed during the production process (for example, the play of the bearing is narrowed). Before the overmolding, the ball bearing can have an increased play of the bearing, which is matched to the compression during overmolding. The ball bearing can have an optimized play of the bearing after overmolding.

[0064] The roller body has rounded V-grooves, which results in an improved notch effect in the notch base.

[0065] In the manufacturing process presented, the shrinkage behavior of the POM material is included in the shape design. For example, the side flanges are inclined further outward in order to compensate for the change that occurs during shrinkage. This has the advantage that no mechanical post-processing is necessary, which simplifies production and maintains the advantageous extrusion surface of the coating.

[0066] The V-rib profile aligned with the wave profile results in a substantially uniform material thickness of the plastic running surface. The wave profile results in a profiled connection between the roller body or the bearing and the plastic running surface.

[0067] During production, at least three injection points or, alternatively, a diaphragm gate, are used for the injection to ensure even concentricity. In the case of small diameters, the bearing can be overmolded when it is fully assembled. With larger diameters, the bearing can be pressed into the roller body functioning as a mantle. The roller body can be coated prior to injection molding to improve the plastics material bonding.

[0068] Finally, it should be noted that terms such as “comprising,” “having,” etc. do not preclude other elements or steps, and terms such as “a” or “an” do not preclude a plurality.

[0069] In accordance with the provisions of the patent statutes, the present invention has been described in what is considered to represent its preferred embodiment. However, it should be noted that the invention can be practiced otherwise than as specifically illustrated and described without departing from its spirit or scope.