BELT-TYPE TRACTION MEANS AND METHOD FOR FABRICATING THE TRACTION MEANS AS WELL AS USE OF SAID TRACTION MEANS IN AN ELEVATOR AND AN ELEVATOR PROVIDED WITH SAID TRACTION MEANS

Abstract

The object of the invention is a belt-type traction means, which comprises a herringbone toothed belt, which has at least a tooth part and a support structure supporting the tooth part, which support structure comprises a plurality of reinforcement means in the longitudinal direction of the toothed belt. In the transverse direction of the toothed belt the toothed belt comprises two edge parts side by side and a center part between the edge parts connecting the edge parts, the spring constant of which center part in the transverse direction of the toothed belt is smaller than the corresponding spring constant of the edge parts. In addition, the object of the invention is a method for fabricating the aforementioned traction means and the use of the traction means in an elevator as well as an elevator provided with the aforementioned traction means.

Claims

1. Belt-type traction means, which comprises a herringbone toothed belt, which has at least a tooth part and a support structure supporting the tooth part, which support structure comprises a plurality of reinforcement means in the longitudinal direction of the toothed belt, wherein in the transverse direction of the toothed belt the toothed belt comprises two edge parts side by side and a center part between the edge parts and connecting the edge parts, the spring constant of which center part in the transverse direction of the toothed belt is smaller than the corresponding spring constant of the edge parts.

2. Traction means according to claim 1, wherein the thickness of the center part is equal to, or smaller than, the thickness of the support structure of the edge parts.

3. Traction means according to claim 1, wherein the center part is of a different material than the edge parts and the material of the center part is both softer and more flexible than the material of the edge parts.

4. Traction means according to claim 1, wherein the center part is fastened at its sides to the side surface of the support structure of each edge part in between the two edge parts situated side by side, in the center of the toothed belt in the direction of the cross-section of the toothed belt.

5. Traction means according to claim 1, wherein the center part is one and the same material as the support structure of the edge parts and the thickness of the center part is smaller than the thickness of the support structure at the point of the edge parts.

6. Traction means according to claim 1, wherein the center part, being more flexible the edge parts, is adapted to allow widening of the toothed belt at the point of the meshing teeth.

7. Method for fabricating a belt-type traction means, which traction means comprises a herringbone toothed belt, which has at least a tooth part and a support structure supporting the tooth part, which support structure comprises a plurality of reinforcement means in the longitudinal direction of the toothed belt, wherein in the width direction of the toothed belt an edge part with support structure and teeth is disposed on each edge of the toothed belt and also a center part is formed between the edge parts in the center of the toothed belt, the spring constant of which center part in the width direction of the toothed belt is smaller than the corresponding spring constant of the edge parts.

8. Method according to claim 7, wherein the center part, being essentially more flexible than the edge parts, being composed of a different material with respect to the edge parts and having a spring constant smaller than the spring constant of the edge parts, is fastened at its sides to the side surfaces that are opposite each other of the support structures of the edge parts.

9. Method according to claim 8, wherein the center part is fastened at its sides to the side surfaces that are opposite each other of the support structures of the edge parts by gluing, welding, vulcanizing or some other suitable fastening method.

10. Method according to claim 7, wherein the support structure of the toothed belt is made to be essentially the width of the whole toothed belt and the center part is formed in such a way that a thinning groove in the longitudinal direction of the toothed belt is formed in the support structure of the toothed belt in the center of the toothed belt in the cross-section of the toothed belt, at the point of which thinning groove the otherwise solid support structure is thinner than at the point of the edge parts of the toothed belt.

11. Method according to claim 10, wherein the thinning groove is formed on the front surface of the support structure, i.e. on the side of the teeth.

12. Method according to claim 11, wherein when forming the thinning groove in the front surface of the support structure, i.e. on the side of the teeth, the groove between the teeth is made at the same time.

13. Method according to claim 10, wherein the thinning groove is formed on the rear surface of the support structure, i.e. on the opposite side to the teeth.

14. Method according to claim 10, wherein the thinning groove is formed in the support structure either in conjunction with forming the profile of the toothed belt, e.g. by casting or otherwise molding, or later, e.g. by cutting or milling.

15. Method according to claim 7, wherein the center part, being more flexible the edge parts, is adapted to allow widening of the toothed belt at the point of the meshing teeth.

16. Use of a herringbone toothed belt functioning as the traction means presented in claim 1 above in an elevator for moving an elevator car and at least one compensating weight, separated from the suspension means of the elevator.

17. Elevator, comprising at least an elevator car, drive machinery supported in its position in relation to the elevator hoistway for achieving movement of the elevator car and a herringbone toothed belt, functioning as a traction means for transmitting rotational movement produced by the drive machinery into movement of the elevator car, which toothed belt has at least a tooth part and a support structure supporting the tooth part, which support structure comprises a plurality of reinforcement means in the longitudinal direction of the toothed belt, wherein in the width direction of the traction means the toothed belt comprises two edge parts side by side and a center part between the edge parts and connecting the edge parts, the spring constant of which center part in the transverse direction of the toothed belt is smaller than the corresponding spring constant of the edge parts.

18. Elevator according to claim 17, wherein the center part, being more flexible the edge parts, is adapted to allow widening of the toothed belt at the point of the meshing teeth.

Description

[0011] In the following, the invention will be described in more detail by the aid of some examples of its embodiment with reference to the simplified and diagrammatic drawings attached, wherein

[0012] FIG. 1 presents an oblique view from the top and side of a short sectioned part of one traction means according to the invention,

[0013] FIG. 2 presents an end view of another sectioned traction means according to the invention,

[0014] FIG. 3 presents an end view of a third sectioned traction means according to the invention, and

[0015] FIG. 4 presents a simplified and diagrammatic side view of one elevator arrangement, in which a traction means according to the invention is used and in which the hoisting machine of the elevator is disposed in the bottom part of the elevator hoistway.

[0016] FIGS. 1-3 present simplified and cross-sectioned views of various herringbone toothed belts, according to the invention, functioning as a traction means 1. What is common to all the different toothed belts 1 is that in the cross-section direction, i.e. in the width direction, of the toothed belt 1 the edge parts 2, with teeth 2b, of them is reinforced to withstand forces in the longitudinal and transverse directions of the toothed belt 1 whereas in the cross-section direction the toothless center part 4 in the center of the toothed belt 1 between the side edges 2 is arranged to flex more, at least in the transverse direction of the toothed belt 1, than the edge parts 2 of the toothed belt 1. In this case the spring constant of the center part 4 between the edge parts 2 and connecting the edge parts 2 is smaller in the transverse direction of the toothed belt 1 than the corresponding spring constant of the edge parts 2.

[0017] There are no teeth 2b at the point of the center part 4, so that in the cross-section at the point of the center part 4 is a groove 2c the length of the toothed belt 1, the depth of the groove being essentially the height of the teeth 2b or deeper. The teeth 2b on both edge parts 2 are similar to each other and as viewed from above they form an angle of the same magnitude as each other to the longitudinal centerline of the toothed belt 1 but on opposite sides of the longitudinal centerline.

[0018] FIG. 1 presents an oblique top view of a short part of one herringbone toothed belt 1 according to the invention, which is composed in cross-section of three parts side by side, i.e. a first edge part 2 and a second edge part 2 as well as a center part 4 between them in the center of the toothed belt 1 in the cross-section direction of the toothed belt 1, the center part being e.g. glued or otherwise fastened at its sides to the support structure 2a functioning as the back of the edge parts 2. In the structure according to FIG. 1 the thickness of the center part 4 is smaller than the thickness of the support structure 2a of the edge parts 2, in which case the flexing property of the center part 4 is enhanced.

[0019] Both edge parts 2 are composed of a support structure 2a, which is provided with teeth 2b that are at an inclined attitude with respect to the direction of travel of the toothed belt 1. Inside a support structure 2a is a plurality of load-bearing reinforcement means 3 side by side, such as metal wires or corresponding means in the longitudinal direction of the toothed belt 1. The reinforcement means 3 are side by side at regular intervals from each other in the support structure 2a and they are arranged in the longitudinal of the toothed belt 1 essentially on a plane in the direction of the plane of the support structure 2a of the toothed belt 1.

[0020] The support structure 2a of the edge parts 2 and the teeth 2b are of a strong and wear-resistant and essentially hard material, such as of an elastomer suited to the purpose. Correspondingly, the center part 4 is of a softer material than the support structure 2a of the edge parts 2, e.g. of some elastomer suited to the purpose, and is arranged to function as a transverse spring in the toothed belt 1, the spring having a spring constant smaller than the spring constant of the support structure 2a of the edge parts 2, and which in this case permits widening of the toothed belt 1 in its transverse direction at the point of meshing teeth 2b that are heavily loaded. In this case the belt force is distributed to a number of teeth 2b and the reinforcement means 3 inside the support structure 2a can stretch to be slightly longer without the tooth forces becoming excessive.

[0021] FIG. 2 presents an end view of a second sectioned toothed belt according to the invention, the belt functioning as a traction means 1. This toothed belt 1 is otherwise similar to the toothed belt presented in FIG. 1, but in this structure the thickness of the center part 4, which is of a different material, is essentially the same as the thickness of the support structure 2a of the edge parts 2. In other respects this belt solution is, however, essentially similar in structure and in function as the belt solution according to FIG. 1.

[0022] FIG. 3 presents an end view of a third sectioned toothed belt 1 according to the invention, the belt functioning as a traction means. This toothed belt 1 is otherwise similar to the toothed belt presented in FIG. 1, but in this structure the center part 4 is the same material as the support structure 2a of the edge parts 2, which support structure in this solution is essentially width of the whole toothed belt 1. The center part 4 differs, however, from the edge parts 2 of the toothed belt 1 in that there are no reinforcement means 3 in the center part 4 and the thickness of the center part 4 is essentially smaller than the thickness of the support structure 2a in the edge parts 2 of the toothed belt 1, because in the center part 4 is a thinning groove 5 thinning the support structure 2a. The groove 2c between the teeth 2b in the center of the toothed belt 1 is in this solution now deeper by the amount of the depth of the thinning groove 5 and the base of the groove 2c extends to below the bottom plane of the teeth 2b inside the support structure 2a. The thinning groove 5 can be either on the front surface of the support structure 2a of the toothed belt 1, i.e. on the side of the teeth 2b, or on the rear surface of the support structure 2a of the toothed belt 1, i.e. on the opposite side to the teeth 2b. The thinner center part 4 without reinforcement means 3 now forms an area more flexible than the edge parts 2 in the lateral direction, i.e. in the width direction, of the toothed belt 1, the spring constant of which area in the width direction of the toothed belt 1 is smaller than the spring constant of the thicker edge parts 2.

[0023] The toothed belt 1 according to the invention is fabricated with the method according to the invention e.g. in such a way that in the cross-section an edge part 2 with support structure 2a and teeth 2b is disposed on each edge of the toothed belt 1 and also a center part 4 is formed between the edge parts 2 in the center of the toothed belt 1, the spring constant of which center part in the width direction of the toothed belt 1 is smaller than the corresponding spring constant of the edge parts 2, and which center part 4 is arranged to flex in the transverse direction of the toothed belt 1 more than the edge parts 2 of the toothed belt 1.

[0024] In the solutions according to FIGS. 1 and 2 the toothed belt 1 is fabricated in such a way that the center part 4, being essentially more flexible than the edge parts 2, being composed of a different material with respect to the edge parts 2 and having a spring constant smaller than the spring constant of the edge parts 2, is fastened at its sides to the side surfaces that are opposite each other of the support structures 2a of the edge parts 2 in between the support structures 2a. The fastening is done e.g. by gluing, vulcanizing or by some other method suited to fastening elastomers.

[0025] Correspondingly, in the solution according to FIG. 3 the toothed belt 1 is fabricated in such a way that a thinning groove 5 in the longitudinal direction of the toothed belt 1 is formed in the support structure 2a of the toothed belt 1 in the center of the toothed belt 1 in the cross-section of the toothed belt 1, at the point of which thinning groove the support structure 2a is thinner than at the point of the edge parts 2 of the toothed belt 1. The thinning groove 5 can be made either on the front surface of the support structure 2a of the toothed belt 1, i.e. on the side of the teeth 2b, or on the rear surface of the support structure 2a of the toothed belt 1, i.e. on the opposite side to the teeth 2b. If the thinning groove 5 is formed on the side of the teeth 2b, the groove 2c between the teeth 2b can be made in conjunction with forming it. The thinning groove 5 is formed either in conjunction with forming the profile of the toothed belt 1, e.g. by casting or otherwise molding, or later, e.g. by cutting or milling.

[0026] The size, strength properties, spring constants and materials of the center part 4 and edge parts 2 of the toothed belt 1 can be varied in many different ways for interadjustment of the transverse flexing of the center part 4 and edge parts 2 of the toothed belt 1.

[0027] FIG. 4 presents a simplified and partially sectioned side view of one elevator arrangement, in which is used a herringbone toothed belt, according to the invention, functioning as a traction means 1. Both the elevator car 6 and the compensating weight or counterweight 7, hereinafter for the sake of simplicity just compensating weight 7, are suspended with 1:1 suspension in such a way that the suspension ropes 8 of the elevator car 6 are led to travel from the elevator car 6 via the diverting pulleys 9 in the top part of the elevator hoistway to compensating weights 7 traveling on their own guide rails, to which compensating weights the second ends of the suspension ropes 8 are fastened.

[0028] In a solution using a traction means 1 according to the invention, the suspension and the moving of the elevator car 6 and the compensating weight 7 are separated from each other, in which case moving is implemented by means of a separate traction means 1, the first end of which traction means 1 is fixed to its fixing point 14 on the bottom part of the elevator car 6 and the second end to its fixing point 15 on the bottom part of the compensating weight 7. The traction means 1 is led from the fixing point 14 of its first end under the bottom of the herringbone traction sheave 10 of the elevator machine 11 that is in the bottom part of the elevator hoistway, e.g. on the floor 13 of the elevator hoistway, to the diverting pulley 12, and after passing around the bottom of which diverting pulley 12 the traction means 1 is led to the fixing point 15 of the second end on the bottom part of the compensating weight 7. The contact between the traction sheave and the traction means transmits the force moving the traction means to the traction means primarily via the toothing of the traction means. The traction means deflects on the traction sheave by the amount of the angle of contact between them. The elevator machine 11 can be geared or gearless.

[0029] In connection with the fixing point 14 of the first end of a traction means 1 is also a tensioning means 14a of the traction means 1, the purpose of which tensioning means is to keep the traction means 1 sufficiently taut from the viewpoint of operational functionality. The tensioning means 14a could just as well be only in connection with the fixing point 15 of the second end of the traction means 1 or also at both ends of the traction means 1.

[0030] The traction means 1 is in this elevator embodiment a herringbone toothed belt, which receives its kinetic energy from the traction sheave 10 by means of shape-locking. Additionally, the traction means 1 is structurally such that a center part 4 is in the center of the traction means 1 in the cross-section of the traction means 1, the center part being arranged to flex in the transverse direction, i.e. in the width direction, of the traction means 1 more than the edge parts 2 of the traction means 1, in which case the belt force acting in the traction means 1 is distributed more evenly on the herringbone toothing of the traction sheave 10.

[0031] The use of the traction means 1 according to the invention is not restricted solely to use of the elevator solution presented above, but instead the same traction means 1 can just as well be used in very different elevator solutions. Instead of one traction means 1 and the other components connected to it, there can be e.g. two side by side, and there can also be two compensating weights 7 side by side. In addition, the suspension ratio and traction ratio can also be other than 1:1, e.g. 2:1.

[0032] The elevator of FIG. 4 can also be realized in some other way, e.g. in such a way that the traction sheave is in the top part of the elevator hoistway instead of a diverting pulley.

[0033] FIG. 4 presents the traction sheave and the traction means in such a way that their angle of contact is 90 degrees. The elevator according to the invention can also be implemented using another contact angle. By arranging the mutual passage of the belt and the traction sheave otherwise, e.g. by means of a diverting pulley or diverting pulleys, an angle of contact of 180 degrees, or even more, can easily be achieved.

[0034] It must also be noted that the different solutions and features presented above can be inventive features together with one or more other features of the invention.

[0035] It is obvious to the person skilled in the art that the invention is not limited solely to the examples described above, but that it may be varied within the scope of the claims presented below. Thus, for example, the attitude and shape of a tooth can be different to what is presented above and the structure, shape, size, number, location and material of the reinforcement means in the support structure of the belt can be different to what is presented above. Thus, for example, the material of the reinforcement means, can instead of steel, be e.g. carbon fiber, glass fiber, Kevlar, an artificial substance, preferably Aramid, or combinations of one or more of the aforementioned, or some other metallic or non-metallic material suited to the purpose. The reinforcement means can be braiding, weave, fiber bundles, wire bundles, metallic or non-metallic tension rods or a composite structure receiving tension.